🔰 What is ERC20 ? - in layman terms as per my capability👈😏

                         To properly understand the purpose of the ERC20 protocol let me take you to the early days of the internet. Back in the early days of the internet, communication between any two applications was very difficult as each programmer was creating their own custom code that only he/she understands, so in order for one application created bysay, programmer A to communicate with another application created by some another programmer say B, Programmer A must have a thorough and proper understanding of the code written by Programmer B. And this caused a lot of problems as it was time-consuming and inefficient and ultimately hindered the scalability of the internet.
                         So in order to make the internet quickly scalable, there was a need for some guidelines or common grounds which each application on the internet must adhere to in order to communicate with each other through the internet. Following these guidelines, programmers can create applications without bothering about the in-depth understanding of other applications working. These guidelines are today's protocols like HTTP, FTP etc we use in our day to day life. Creation of these protocols gave the early internet the scalability boost it required to become what it is today.

                         Same way as the internet, in the early days of Ethereum, developers creating tokens on Ethereum were completely free to implement whatever functions they require and however they require, for example say a developer create a Token A on Ethereum with having a token transfer function named transfer_A and another developer create another Token B having a transfer token function named transfer_B. These cause problems similar to what the internet faced long ago. As you can see both the tokens are having different transfer functions, named different or may function wise different too. The problem arises when these token are listed on exchanges. As the structure of both the tokens A and B are different, the exchanges, in order to interact with each of the tokens, need to write custom code for each of the tokens, which was cumbersome and inefficient as a lot of new tokens began to emerge. This was hindering the scalability and so the Ethereum platform required some sort of standards or guidelines for tokens.

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                         The standard they came up with is ERC20. Tokens create following these standards are known as ERC20 tokens and these solved a lot of the issues like now exchanges can write code only once and interact with all the ERC20 token without any modificationsto their current code, and these you may have noticed on My Ether Wallet on which every ERC20 token is available as soon it's created without having to write any further code. All this gave a boost in token interoperability among ERC20 tokens on the Ethereum platform and for exchanges ERC20 is acting like some sort of Swiss Army Knife.

^{Gif prepared by Pankaj Borah}

• totalSupply- this method defines the total supply of a token. When this limit is reached the smart contract will not create any further new tokens.

• balanceOf - this method returns the no of tokens a given address has. You can compare this to checking any eth wallet balance on etherscan.

• transfer - this method is used to transfer a given amount of token from the total supply to a user.

• transferFrom - this method is used to transfer tokens between any two users.

• approve - this verifies if the contract can give a certain amount of token to a user taking into account the total supply.

• allowance - this verifies if a user has sufficient balance to send to a certain amount of token to another user.

                         So as you can see if the token creator implements the above guidelines for creating the contract then the token is considered and ERC20 token.Apart from these the creator can implement additional functionality as per his/her wish. With this I am wrapping up this article my friend. See you another time and as always, thanks your reading.😉