ERC-20 tokens are fungible, like real-world currency, where each unit is interchangeable with any other. ERC-721 tokens, on the other hand, are non-fungible and represent unique items or assets.
ERC-1155 combines these functionalities. It allows for the creation of both fungible and non-fungible tokens within a single smart contract, with each token identified by an ID. It reduces the amount of data and code required for token transactions, thereby saving on gas fees and making operations more gas-efficient.
This versatility makes ERC-1155 ideal for various use cases, particularly in the gaming and digital collectibles sectors. For instance, in a gaming ecosystem, a single ERC-1155 contract could govern various types of tokens - representing game currency, unique characters, weaponry, skins, and more.