Non-fungibility is a good thing since collectable tokens increase in value the more rare they are.
There are two major standards for Ethereum tokens: ERC-20 versus ERC-721.
It is crucial that Dapps created on top of Ethereum to interact fluidly with one another to form a healthy ecosystem. In the above situation, one of the tokens may be an alpha smart contract and the other a beta smart contract.
This implies that if the developers want the two tokens to interact, they will need to pay close attention to the details of both contracts, and identify precisely how the two tokens will operate together.
This might be interpreted as meaning that scalability will be an issue because of this.
As long as there are 100 distinct tokens with 100 separate contracts, you will need a massive number of sophisticated mathematics to search down and make sure transfers can go through between all of them. This is the opposite of perfect.
This is why the architecture of the token was standardised, as a result of which decisions had to be made. ERC-20 sets of regulations are commonly referred to as the Building Blocks. The “ERC” is a request for comment that was posted on the Ethereum GitHub repository; the number '20' is allocated to this request.