Here’s why that’s baloney

Mark Cuban popularized entrepreneurship.

Shark Tank (which made Mark famous) made starting a business glamorous to attract more entrepreneurs. First off

This isn't an anti-billionaire rant.

Mark Cuban has done excellent. He's a smart, principled businessman. I enjoy his Web3 work. But Mark's work and productivity theories are absurd.

You don't need to outwork everyone in this recession to live well.

You won't be able to outwork me.

Yuck! Mark's words made me gag.

Why do boys think working is a football game where the winner wins a Super Bowl trophy? To outwork you.

Hard work doesn't equal intelligence.

Highly clever professionals spend 4 hours a day in a flow state, then go home to relax with family.

If you don't put forth the effort, someone else will.

- Mark.

He'll burn out. He's delusional and doesn't understand productivity. Boredom or disconnection spark our best thoughts.

TikTok outlaws boredom.

In a spare minute, we check our phones because we can't stand stillness.

All this work p*rn makes things worse. When is it okay to feel again? Because I can’t feel anything when I’m drowning in work and haven’t had a holiday in 2 years.

Your rivals are actively attempting to undermine you.

Ohhh please Mark…seriously.

This isn't a Tom Hanks war film. Relax. Not everyone is a rival. Only yourself is your competitor. To survive the recession, be better than a year ago.

If you get rich, great. If not, there's more to life than Lambos and angel investments.

Some want to relax and enjoy life. No competition. We witness people with lives trying to endure the recession and record-high prices.

This fictitious rival worsens life and work.

If you are truly talented, you will motivate others to work more diligently and effectively.

No Mark. Soz.

If you're a good leader, you won't brag about working hard and treating others like cogs. Treat them like humans. You'll have EQ.

Silly statements like this are caused by an out-of-control ego. No longer watch Shark Tank.

Ego over humanity.

Good leaders will urge people to keep together during the recession. Good leaders support those who are laid off and need a reference.

Not harder, quicker, better. That created my mental health problems 10 years ago.

Truth: we want to work less.

The promotion of entrepreneurship is ludicrous.

Marvel superheroes. Seriously, relax Max.

I used to write about entrepreneurship, then I quit. Many WeWork Adam Neumanns. Carelessness.

I now utilize the side hustle title when writing about online company or entrepreneurship. Humanizes.

Stop glorifying. Thinking we'll all be Elon Musks who send rockets to Mars is delusional. Most of us won't create companies employing hundreds.

OK.

The true epidemic is glorification. fewer selfies Little birdy needs less bank account screenshots. Less Uber talk.

We're exhausted.

Fun, ego-free business can transform the world. Take a relax pill.

Work as if someone were attempting to take everything from you.

I've seen people lose everything.

Myself included. My 20s startup failed. I was almost bankrupt. I thought I'd never recover. Nope.

Best thing ever.

Losing everything reveals your true self. Unintelligent entrepreneur egos perish instantly. Regaining humility revitalizes relationships.

Money's significance shifts. Stop chasing it like a puppy with a bone.

Fearing loss is unfounded.

Here is a more effective approach than outworking nobody.

(You'll thrive in the recession and become wealthy.)

Smarter work

Overworking is donkey work.

You don't want to be a career-long overworker. Instead than wasting time, write down what you do. List tasks and processes.

Keep doing/outsource the list. Step-by-step each task. Continuously systematize.

Then recruit a digital employee like Zapier or a virtual assistant in the same country.

Intelligent, not difficult.

If your big break could burn in hell, diversify like it will.

People err by focusing on one chance.

Chances can vanish. All-in risky. Instead of working like a Mark Cuban groupie, diversify your income.

If you're employed, your customer is your employer.

Sell the same abilities twice and add 2-3 contract clients. Reduce your hours at your main job and take on more clients.

Leave brand loyalty behind

Mark desires his employees' worship.

That's stupid. When times are bad, layoffs multiply. The problem is the false belief that companies care. No. A business maximizes profit and pays you the least.

To care or overpay is anti-capitalist (that run the world). Be honest.

I was a banker. Then the bat virus hit and jobs disappeared faster than I urinate after a night of drinking.

Start being disloyal now since your company will cheerfully replace you with a better applicant. Meet recruiters and hiring managers on LinkedIn. Whenever something goes wrong at work, act.

Loyalty to self and family. Nobody.

Outwork this instead

Mark doesn't suggest outworking inflation instead of people.

Inflation erodes your time on earth. If you ignore inflation, you'll work harder for less pay every minute.

Financial literacy beats inflation.

Get a side job and earn money online

So you can stop outworking everyone.

Internet leverages time. Same effort today yields exponential results later. There are still whole places not online.

Instead of working forever, generate money online.

Final Words

Overworking is stupid. Don't listen to wealthy football jocks.

Work isn't everything. Prioritize diversification, internet income streams, boredom, and financial knowledge throughout the recession.

That’s how to get wealthy rather than burnout-rich.

Ready to quit full-time? No worries.

Baby Boomer retirement has accelerated since COVID-19 began. In 2020, 29 million boomers retire. Over 3 million more than in 2019. 75 million Baby Boomers will retire by 2030.

First, quit your work to enjoy retirement. Leave a professional legacy. Your retirement will start well. It all starts with a retirement letter.

Retirement Letter

Retirement letters are formal resignation letters. Different from other resignation letters, these don't tell your employer you're leaving. Instead, you're quitting.

Since you're not departing over grievances or for a better position or higher income, you may usually terminate the relationship amicably. Consulting opportunities are possible.

Thank your employer for their support and give them transition information.

Resignation letters aren't merely a formality. This method handles wages, insurance, and retirement benefits.

Retirement letters often accompany verbal notices to managers. Schedule a meeting before submitting your retirement letter to discuss your plans. The letter will be stored alongside your start date, salary, and benefits in your employee file.

Retirement is typically well-planned. Employers want 6-12 months' notice.

Summary

• Guidelines for Giving Retirement Notice

• Components of a Successful Retirement Letter

• Template for Retirement Letter

• Ideas for Samples of Retirement Letters

• First Example of Retirement Letter

• Second Example of Retirement Letter

• Third Example of Retirement Letter

• Fourth Example of Retirement Letter

• Fifth Example of Retirement Letter

• Sixth Example of Retirement Letter

• Seventh Example of Retirement Letter

• Eighth Example of Retirement Letter

• Ninth Example of Retirement Letter

• Tenth Example of Retirement Letter

• Frequently Asked Questions

• 1. What is a letter of retirement?

• 2. Why should you include a letter of retirement?

• 3. What information ought to be in your retirement letter?

• 4. Must I provide notice?

• 5. What is the ideal retirement age?

Guidelines for Giving Retirement Notice

While starting a new phase, you're also leaving a job you were qualified for. You have years of experience. So, it may not be easy to fill a retirement-related vacancy.

Talk to your boss in person before sending a letter. Notice is always appreciated. Properly announcing your retirement helps you and your organization transition.

How to announce retirement:

• Learn about the retirement perks and policies offered by the company. The first step in figuring out whether you're eligible for retirement benefits is to research your company's retirement policy.

• Don't depart without providing adequate notice. You should give the business plenty of time to replace you if you want to retire in a few months.

• Help the transition by offering aid. You could be a useful resource if your replacement needs training.

• Contact the appropriate parties. The original copy should go to your boss. Give a copy to HR because they will manage your 401(k), pension, and health insurance.

• Investigate the option of working as a consultant or part-time. If you desire, you can continue doing some limited work for the business.

• Be nice to others. Describe your achievements and appreciation. Additionally, express your gratitude for giving you the chance to work with such excellent coworkers.

• Make a plan for your future move. Simply updating your employer on your goals will help you maintain a good working relationship.

• Use a formal letter or email to formalize your plans. The initial step is to speak with your supervisor and HR in person, but you must also give written notice.

Components of a Successful Retirement Letter

To write a good retirement letter, keep in mind the following:

• A formal salutation. Here, the voice should be deliberate, succinct, and authoritative.

• Be specific about your intentions. The key idea of your retirement letter is resignation. Your decision to depart at this time should be reflected in your letter. Remember that your intention must be clear-cut.

• Your deadline. This information must be in resignation letters. Laws and corporate policies may both stipulate a minimum amount of notice.

• A kind voice. Your retirement letter shouldn't contain any resentments, insults, or other unpleasantness. Your letter should be a model of professionalism and grace. A straightforward thank you is a terrific approach to accomplish that.

• Your ultimate goal. Chaos may start to happen as soon as you turn in your resignation letter. Your position will need to be filled. Additionally, you will have to perform your obligations up until a successor is found. Your availability during the interim period should be stated in your resignation letter.

• Give us a way to reach you. Even if you aren't consulting, your company will probably get in touch with you at some point. They might send you tax documents and details on perks. By giving your contact information, you can make this process easier.

Template for Retirement Letter

Identify

Title you held

Address

Supervisor's name

Supervisor’s position

Company name

HQ address

Date

[SUPERVISOR],

1.

Inform that you're retiring. Include your last day worked.

2.

Employer thanks. Mention what you're thankful for. Describe your accomplishments and successes.

3.

Helping moves things ahead. Plan your retirement. Mention your consultancy interest.

Sincerely,

[Signature]

First and last name

Phone number

Personal Email

Ideas for Samples of Retirement Letters

First Example of Retirement Letter

Martin D. Carey

123 Fleming St

Bloomfield, New Jersey 07003

(555) 555-1234

June 6th, 2022

Willie E. Coyote

President

Acme Co

321 Anvil Ave

Fairfield, New Jersey 07004

Dear Mr. Coyote,

This letter notifies Acme Co. of my retirement on August 31, 2022.

There has been no other organization that has given me that sense of belonging and purpose.

My fifteen years at the helm of the Structural Design Division have given me‌ ‌a‌ ‌strong sense‌ ‌of‌ ‌purpose. I’ve been fortunate to have your support, and I’ll be always grateful for the opportunity you offered me.

I had a difficult time making this decision. ‌As a result of finding a small property in Arizona where we will be able to spend our remaining days together, my wife and I have decided to officially retire.

In spite of my regret at being unable to contribute to the firm we’ve built, I believe it is wise to move on.

My heart will always belong to Acme Co. ‌Thank you for the opportunity and best of luck in the years to come.

Sincerely,

Martin D. Carey

Second Example of Retirement Letter

Gustavo Fring

Los Pollas Hermanos

12000–12100 Coors Rd SW,

Albuquerque, New Mexico 87045

Dear Mr. Fring,

I write this letter to announce my formal retirement from Los Pollas Hermanos as manager, effective October 15.

As an employee at Los Pollas Hermanos, I appreciate all the great opportunities you have given me. ‌It has been a pleasure to work with and learn from my colleagues for the past 10 years, and I am looking forward to my next challenge.

If there is anything I can do to assist during this time, please let me know.

Sincerely,

Linda T. Crespo

Third Example of Retirement Letter

William M. Arviso

4387 Parkview Drive

Tustin, CA 92680

May 2, 2023

Tony Stark

Owner

Stark Industries

200 Industrial Avenue

Long Beach, CA 90803

Dear Tony:

I’m writing to inform you that my final day of work at Stark Industries will be May14, 2023. ‌When that time comes, I intend‌ ‌to‌ ‌retire.

As I embark on this new chapter in my life, I would like to thank you and the entire Stark Industries team for providing me with so many opportunities. ‌You have all been a pleasure to work with and I will miss you all when I retire.

I am glad to assist you with the transition in any way I can to ensure your new hire has a seamless experience. ‌All ongoing projects will be completed until my retirement date, and all key information will be handed over‌ ‌to‌ ‌the‌ ‌team.

Once again, thank you for the opportunity to be part of the Stark Industries team. ‌All the best to you and the team in the days to come.

Please do not hesitate to contact me if you require any additional information. ‌In order to finalize my retirement plans, I’ll meet with HR and can provide any details that may be necessary.

Sincerely,

(Signature)

William M. Arviso

Fourth Example of Retirement Letter

Garcia, Barbara

First Street, 5432

New York City, NY 10001

(1234) (555) 123–1234

1 October 2022

Gunther

Owner

Central Perk

199 Lafayette St.

New York City, NY 10001

Mr. Gunther,

The day has finally arrived. ‌As I never imagined, I will be formally retiring from Central Perk on November 1st, 2022.

Considering how satisfied I am with my current position, this may surprise you. ‌It would be best if I retired now since my health has deteriorated, so I think this is a good time to do so.

There is no doubt that the past‌ ‌two‌ ‌decades‌ ‌have‌ ‌been‌ ‌wonderful. ‌Over the years, I have seen a small coffee shop grow into one of the city’s top‌ ‌destinations.

It will be hard for me to leave this firm without wondering what more success we could have achieved. But I’m confident that you and the rest of the Central Perk team will achieve great things.

My family and I will never forget what you’ve done for us, and I am grateful for the chance you’ve given me. My house is always open to you.

Sincerely Yours

Garcia, Barbara

Fifth Example of Retirement Letter

Pat Williams

618 Spooky Place

Monstropolis, 23221

123–555–0031

pwilliams@email.com

Feb. 16, 2022

Mike Wazowski

Co-CEO

Monters, Inc.

324 Scare Road

Monstropolis

Dear Mr. Wazowski,

As a formal notice of my upcoming retirement, I am submitting this letter. ‌I will be leaving Monters, Inc. on‌ ‌April‌ ‌13.

These past 10 years as a marketing associate have provided me with many opportunities. ‌Since we started our company a decade ago, we have seen the face of harnessing screams change dramatically into harnessing laughter. ‌During my time working with this dynamic marketing team, I learned a lot about customer behavior and marketing strategies. ‌Working closely with some of our long-standing clients, such as Boo, was a particular pleasure.

I would be happy to‌ ‌assist‌ ‌with‌ ‌the‌ ‌transition‌ ‌following‌ ‌my‌ ‌retirement. ‌It would be my pleasure to assist in the hiring or training of‌ ‌my‌ ‌replacement. ‌In order to spend more time with my family, I will also be able to offer part-time consulting services.

After I retire, I plan to cash out the eight unused vacation days I’ve accumulated and take my pension as a lump sum.

Thank you for the opportunity to work with Monters, Inc. ‌In the years to come, I wish you all the best!

Sincerely,

Paul Williams

Sixth Example of Retirement Letter

Dear Micheal,

As In my tenure at Dunder Mifflin Paper Company, I have given everything I had. It has been an honor to work here. But‌ ‌I‌ ‌have‌ ‌decided‌ ‌to‌ ‌move on to new challenges and retire from my position — mainly bears, beets, and Battlestar Galactia.

I appreciate the opportunity to work here and learn so much. During my time at this company, I will always remember the good times and memories we shared. Wishing you all the best in the future.

Sincerely,

Dwight K. Shrute

Your signature

May 16

Seventh Example of Retirement Letter

Greetings, Bill

I am announcing my retirement from Initech, effective March 15, 2023.

Over the course of my career here, I’ve had the privilege of working with so many talented and inspiring people.

In 1999, when I began working as a customer service representative, we were a small organization located in a remote office park.

The fact that we now occupy a floor of the Main Street office building with over 150 employees continues to amaze me.

I am looking forward to spending more time with family and traveling the country in our RV. Although I will be sad to leave.

Please let me know if there are any extra steps I can take to facilitate this transfer.

Sincerely,

Frankin, RenitaEighth Example of Retirement Letter

Height Example of Retirement Letter

Bruce,

Please accept my resignation from Wayne Enterprises as Marketing Communications Director. My last day will be August 1, 2022.

The decision to retire has been made after much deliberation. Now that I have worked in the field for forty years, I believe it is a good time to begin completing my bucket list.

It was not easy for me to decide to leave the company. Having worked at Wayne Enterprises has been rewarding both professionally and personally. There are still a lot of memories associated with my first day as a college intern.

My intention was not to remain with such an innovative company, as you know. I was able to see the big picture with your help, however. Today, we are a force that is recognized both nationally and internationally.

In addition to your guidance, the bold, visionary leadership of our company contributed to the growth of our company.

My departure from the company coincides with a particularly hectic time. Despite my best efforts, I am unable to postpone my exit.

My position would be well served by an internal solution. I have a more than qualified marketing manager in Caroline Crown. It would be a pleasure to speak with you about this.

In case I can be of assistance during the switchover, please let me know. Contact us at (555)555–5555. As part of my responsibilities, I am responsible for making sure all work is completed to Wayne Enterprise’s stringent requirements. Having the opportunity to work with you has been a pleasure. I wish you continued success with your thriving business.

Sincerely,

Cash, Cole

Marketing/Communications

Ninth Example of Retirement Letter

Norman, Jamie

2366 Hanover Street

Whitestone, NY 11357

555–555–5555

jamie.norman@email.com

15 October 2022

Mr. Lippman

Head of Pendant Publishing

600 Madison Ave.

New York, New York

Respected Mr. Lippman,

Please accept my resignation effective‌ ‌November‌ ‌1,‌ ‌2022.

Over the course of my ten years at Pendant Publishing, I’ve had a great deal of fun and I’m quite grateful for all the assistance I’ve received.

It was a pleasure to wake up and go to work every day because of our outstanding corporate culture and the opportunities for promotion and professional advancement available to me.

While‌ ‌I am excited about retiring, I am going to miss being part of our team. ‌It’s my hope that I’ll be able to maintain the friendships I’ve formed here for a long time to come.

In case I can be of assistance prior to or following my departure, please let me know. ‌If I can assist in any way to ensure a smooth transfer to my successor, I would be delighted to do so.

Sincerely,

Signed (hard copy letter)

Norman, Jamie

Tenth Example of Retirement Letter

17 January 2023

Greg S. Jackson

Cyberdyne Systems

18144 El Camino Real,

Sunnyvale, CA

Respected Mrs. Duncan,

I‌ ‌am‌ ‌writing‌ ‌to‌ ‌inform you that I will be resigning from Cyberdyne Systems as of March 1, 2023. I’m grateful to have had this opportunity, and it was a difficult decision to make.

My development as a programmer and as a more seasoned member of the organization has been greatly assisted by your coaching.

I have been proud of Cyberdyne Systems’ ethics and success throughout my 25 years at the company. Starting as a mailroom clerk and currently serving as head programmer.

The portfolios of our clients have always been handled with the greatest care by my colleagues. It is our employees and services that have made Cyberdyne Systems the success it is today.

During my tenure as head of my division, I’ve increased our overall productivity by 800 percent, and I expect that trend to continue after‌ ‌I‌ ‌retire.

In light of the fact that the process of replacing me may take some time, I would like to offer my assistance in any way I can.

The greatest contender for this job is Troy Ledford, my current assistant.

Also, before I leave, I would be willing to teach any partners how to use the programmer I developed to track and manage the development of Skynet.

Over the next few months, I’ll be enjoying vacations with my wife as well as my granddaughter moving‌ ‌to‌ ‌college.

If Cyberdyne Systems has any openings for consultants, please let me know. ‌It has been a pleasure working with you over the last 25 years. I appreciate your concern and care.

Sincerely,

Greg S, Jackson

Questions and Answers

1. What is a letter of retirement?

Retirement letters tell your supervisor you're retiring. This informs your employer that you're departing, like a letter. A resignation letter also requests retirement benefits.

Supervisors frequently receive retirement letters and verbal resignations. Before submitting your retirement letter, meet to discuss your plans. This letter will be filed with your start date, salary, and benefits.

2. Why should you include a letter of retirement?

Your retirement letter should explain why you're leaving. When you quit, your manager and HR department usually know. Regardless, a retirement letter might help you leave on a positive tone. It ensures they have the necessary papers.

In your retirement letter, you tell the firm your plans so they can find your replacement. You may need to stay in touch with your company after sending your retirement letter until a successor is identified.

3. What information ought to be in your retirement letter?

Format it like an official letter. Include your retirement plans and retirement-specific statistics. Date may be most essential.

In some circumstances, benefits depend on when you resign and retire. A date on the letter helps HR or senior management verify when you gave notice and how long.

In addition to your usual salutation, address your letter to your manager or supervisor.

The letter's body should include your retirement date and transition arrangements. Tell them whether you plan to help with the transition or train a new employee. You may have a three-month time limit.

Tell your employer your job title, how long you've worked there, and your biggest successes. Personalize your letter by expressing gratitude for your career and outlining your retirement intentions. Finally, include your contact info.

4. Must I provide notice?

Two-week notice isn't required. Your company may require it. Some state laws contain exceptions.

Check your contract, company handbook, or HR to determine your retirement notice. Resigning may change the policy.

Regardless of your company's policy, notification is standard. Entry-level or junior jobs can be let go so the corporation can replace them.

Middle managers, high-level personnel, and specialists may take months to replace. Two weeks' notice is a courtesy. Start planning months ahead.

You can finish all jobs at that period. Prepare transition documents for coworkers and your replacement.

5. What is the ideal retirement age?

Depends on finances, state, and retirement plan. The average American retires at 62. The average retirement age is 66, according to Gallup's 2021 Economy and Personal Finance Survey.

Remember:

• Before the age of 59 1/2, withdrawals from pre-tax retirement accounts, such as 401(k)s and IRAs, are subject to a penalty.

• Benefits from Social Security can be accessed as early as age 62.

• Medicare isn't available to you till you're 65,

• Depending on the year of your birth, your Full Retirement Age (FRA) will be between 66 and 67 years old.

• If you haven't taken them already, your Social Security benefits increase by 8% annually between ages 6 and 77.

You do not want to miss these

Stop! Stop it! Two things to avoid when starting a YouTube channel. Critical. Possible channel-killers Its future revenue.

I'll tell you now, so don't say "I wish I knew."

The Notorious Copyright Allegation

My YouTube channel received a copyright claim before I sold it. This claim was on a one-minute video I thought I'd changed enough to make mine, but the original owner disagreed.

It cost me thousands in ad revenue. Original owner got the profits.

Well, it wasn't your video, you say.

Touché.

I've learned. Sorta

I couldn't stop looking at the video's views. The video got 1,000,000 views without any revenue. I made 4 more similar videos.

If they didn't get copyrighted, I'd be rolling in dough.

You've spent a week editing and are uploading to YouTube. You're thrilled as you stand and stretch your back. You see the video just before publishing.

No way!

The red exclamation point on checks.

Copyright claim!

YouTube lets you publish, but you won't make money.

Sounds fair? Well, it is.

Copyright claims mean you stole someone's work. Song, image, or video clip.

We wouldn't want our content used for money.

The only problem with this is that almost everything belongs to someone else. I doubt some of the biggest creators are sitting down and making their music for their videos. That just seems really excessive when you could make a quick search on YouTube and download a song (I definitely don’t do this because that would be stealing).

So how do you defeat a copyright defense?

Even copyright-free songs on YouTube aren't guaranteed. Some copyrighted songs claim to be free.

Use YouTube's free music library or pay for a subscription to adobe stock, epidemic sound, or artlist.io.

Most of my videos have Nintendo music. Almost all game soundtracks are copyright-free and offer a variety of songs.

Restriction on age

Age restrictions are a must-avoid. A channel dies.

YouTube never suggests age-restricted videos.

Shadow banning means YouTube hides your content from subscribers and non-subscribers.

Keeping your channel family-friendly can help.

I hear you complaining that your channel isn't for kids. I agree. Not everyone has a clean mouth or creates content for minors.

YouTube has changed rapidly in recent years. Focusing on kids. Fewer big creators are using profanity or explicit content in videos. Not YouTube-worthy.

Youtube wants to be family-friendly. A family-friendly movie. It won't promote illegal content. Yes, it allows profanity.

Do I recommend avoiding no-no words in videos? Never. Okay. YouTube's policies are shaky. YouTube uses video content to determine ad suitability.

No joke. If you're serious about becoming a content creator, avoid profanity and inappropriate topics.

If your channel covers 18+ topics, like crime or commentary, censor as much as possible.

YouTube can be like walking on eggshells. You never know what is gonna upset the boss. So play it safe and try to avoid getting on their bad side.

Mr. Beast, Dream, Markplier, Faze Rug, and PewDewPie are popular creators. They maintain it family-friendly while entertaining fans.

You got this.

ERC165 (or EIP-165) is a standard utilized by various open-source smart contracts like Open Zeppelin or Aavegotchi.

What's it? You must implement? Why do we need it? I'll describe the standard and answer any queries.

What is ERC165

ERC165 detects and publishes smart contract interfaces. Meaning? It standardizes how interfaces are recognized, how to detect if they implement ERC165, and how a contract publishes the interfaces it implements. How does it work?

Why use ERC165? Sometimes it's useful to know which interfaces a contract implements, and which version.

Identifying interfaces

An interface function's selector. This verifies an ABI function. XORing all function selectors defines an interface in this standard. The following code demonstrates.

// SPDX-License-Identifier: UNLICENCED
pragma solidity >=0.8.0 <0.9.0;

interface Solidity101 {
    function hello() external pure;
    function world(int) external pure;
}

contract Selector {
    function calculateSelector() public pure returns (bytes4) {
        Solidity101 i;
        return i.hello.selector ^ i.world.selector;
        // Returns 0xc6be8b58
    }

    function getHelloSelector() public pure returns (bytes4) {
        Solidity101 i;
        return i.hello.selector;
        // Returns 0x19ff1d21
    }

    function getWorldSelector() public pure returns (bytes4) {
        Solidity101 i;
        return i.world.selector;
        // Returns 0xdf419679
    }
}

This code isn't necessary to understand function selectors and how an interface's selector can be determined from the functions it implements.

Run that sample in Remix to see how interface function modifications affect contract function output.

Contracts publish their implemented interfaces.

We can identify interfaces. Now we must disclose the interfaces we're implementing. First, import IERC165 like so.

pragma solidity ^0.4.20;

interface ERC165 {
    /// @notice Query if a contract implements an interface
    /// @param interfaceID The interface identifier, as specified in ERC-165
    /// @dev Interface identification is specified in ERC-165. 
    /// @return `true` if the contract implements `interfaceID` and
    ///  `interfaceID` is not 0xffffffff, `false` otherwise
    function supportsInterface(bytes4 interfaceID) external view returns (bool);
}

We still need to build this interface in our smart contract. ERC721 from OpenZeppelin is a good example.

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/ERC721.sol)

pragma solidity ^0.8.0;

import "./IERC721.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/introspection/ERC165.sol";
// ...

contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
  // ...

  function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
    return
      interfaceId == type(IERC721).interfaceId ||
      interfaceId == type(IERC721Metadata).interfaceId ||
      super.supportsInterface(interfaceId);
  }
  
  // ...
}

I deleted unnecessary code. The smart contract imports ERC165, IERC721 and IERC721Metadata. The is keyword at smart contract declaration implements all three.

Kind (interface).

Note that type(interface).interfaceId returns the same as the interface selector.

We override supportsInterface in the smart contract to return a boolean that checks if interfaceId is the same as one of the implemented contracts.

Super.supportsInterface() calls ERC165 code. Checks if interfaceId is IERC165.

function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
    return interfaceId == type(IERC165).interfaceId;
}

So, if we run supportsInterface with an interfaceId, our contract function returns true if it's implemented and false otherwise. True for IERC721, IERC721Metadata, andIERC165.

Conclusion

I hope this post has helped you understand and use ERC165 and why it's employed.

Have a great day, thanks for reading!

Know why it's important.

The entrepreneur I was meeting with said, "I should be doing crypto, or maybe AI? Aren't those the hot spots? I should look there for a startup idea.”

I shook my head. Yes, they're exciting, but that doesn't mean they're best for you and your business.

“There are different types of entrepreneurs?” he asked.

I said "obviously." Two types, actually. Knowing what type of entrepreneur you are helps you build the right startup.

The two types of businesspeople

The best way for me to describe the two types of entrepreneurs is to start by telling you exactly the kinds of entrepreneurial opportunities I never get excited about: future opportunities.

In the early 1990s, my older brother showed me the World Wide Web and urged me to use it. Unimpressed, I returned to my Super Nintendo.

My roommate tried to get me to join Facebook as a senior in college. I remember thinking, This is dumb. Who'll use it?

In 2011, my best friend tried to convince me to buy bitcoin and I laughed.

Heck, a couple of years ago I had to buy a new car, and I never even considered buying something that didn’t require fossilized dinosaur bones.

I'm no visionary. I don't anticipate the future. I focus on the present.

This tendency makes me a problem-solving entrepreneur. I identify entrepreneurial opportunities by spotting flaws and/or inefficiencies in the world and devising solutions.

There are other ways to find business opportunities. Visionary entrepreneurs also exist. I don't mean visionary in the hyperbolic sense that implies world-changing impact. I mean visionary as an entrepreneur who identifies future technological shifts that will change how people work and live and create new markets.

Problem-solving and visionary entrepreneurs are equally good. But the two approaches to building companies are very different. Knowing the type of entrepreneur you are will help you build a startup that fits your worldview.

What is the distinction?

Let's use some simple hypotheticals to compare problem-solving and visionary entrepreneurship.

Imagine a city office building without nearby restaurants. Those office workers love to eat. Sometimes they'd rather eat out than pack a lunch. As an entrepreneur, you can solve the lack of nearby restaurants. You'd open a restaurant near that office, say a pizza parlor, and get customers because you solved the lack of nearby restaurants. Problem-solving entrepreneurship.

Imagine a new office building in a developing area with no residents or workers. In this scenario, a large office building is coming. The workers will need to eat then. As a visionary entrepreneur, you're excited about the new market and decide to open a pizzeria near the construction to meet demand.

Both possibilities involve the same product. You opened a pizzeria. How you launched that pizza restaurant and what will affect its success are different.

Why is the distinction important?

Let's say you opened a pizzeria near an office. You'll probably get customers. Because people are nearby and demand isn't being met, someone from a nearby building will stop in within the first few days of your pizzeria's grand opening. This makes solving the problem relatively risk-free. You'll get customers unless you're a fool.

The market you're targeting existed before you entered it, so you're not guaranteed success. This means people in that market solved the lack of nearby restaurants. Those office workers are used to bringing their own lunches. Why should your restaurant change their habits? Even when they eat out, they're used to traveling far. They've likely developed pizza preferences.

To be successful with your problem-solving startup, you must convince consumers to change their behavior, which is difficult.

Unlike opening a pizza restaurant near a construction site. Once the building opens, workers won't have many preferences or standardized food-getting practices. Your pizza restaurant can become the incumbent quickly. You'll be the first restaurant in the area, so you'll gain a devoted following that makes your food a routine.

Great, right? It's easier than changing people's behavior. The benefit comes with a risk. Opening a pizza restaurant near a construction site increases future risk. What if builders run out of money? No one moves in? What if the building's occupants are the National Association of Pizza Haters? Then you've opened a pizza restaurant next to pizza haters.

Which kind of businessperson are you?

This isn't to say one type of entrepreneur is better than another. Each type of entrepreneurship requires different skills.

As my simple examples show, a problem-solving entrepreneur must operate in markets with established behaviors and habits. To be successful, you must be able to teach a market a new way of doing things.

Conversely, the challenge of being a visionary entrepreneur is that you have to be good at predicting the future and getting in front of that future before other people.

Both are difficult in different ways. So, smart entrepreneurs don't just chase opportunities. Smart entrepreneurs pursue opportunities that match their skill sets.