ERC-20, ERC-721,ERC-1155

1.ERC-20 (Fungible Token – Like Coins) Core Functions -totalSupply → Returns the total number of tokens in existence. -balanceOf(address account)→ Shows how many tokens a specific address owns. -transfer(address to, uint256 amount)→ Sends tokens from your account to another address. -approve(address spender, uint256 amount)→ Authorizes another address to spend your tokens. -allowance(address owner, address spender) → Checks how many tokens a spender is allowed to use from an owner’s account. -transferFrom(address from, address to, uint256 amount)→ Moves tokens from one address to another using the allowance mechanism. Internal Functions _mint(address account, uint256 amount)→ Creates new tokens and adds them to the specified account. _burn(address account, uint256 amount)→ Destroys tokens from the specified account.

2.ERC-721 (Non-Fungible Token – Unique Items) Core Functions -balanceOf(address owner)→ Returns how many NFTs a specific address owns. -ownerOf(uint256 tokenId)→ Returns the current owner of a specific NFT. -approve(address to, uint256 tokenId)→ Grants permission for another address to transfer a specific NFT. -getApproved(uint256 tokenId)→ Returns the address approved to transfer a specific NFT. -setApprovalForAll(address operator, bool approved)→ Allows or revokes another address’s permission to manage all your NFTs. -isApprovedForAll(address owner, address operator)→ Checks if an operator can manage all NFTs of an owner. -transferFrom(address from, address to, uint256 tokenId)→ Transfers ownership of an NFT from one address to another. -safeTransferFrom(address from, address to, uint256 tokenId)→ Safely transfers an NFT, ensuring the recipient can handle it. Internal Functions _mint(address to, uint256 tokenId)→ Creates a new NFT and assigns it to the specified address. _burn(uint256 tokenId)→ Destroys a specific NFT.

3.ERC-1155 (Multi-Token – Mixed Fungible and Non-Fungible) Core Functions -balanceOf(address account, uint256 id)→ Returns how many tokens of a given ID an address owns. -balanceOfBatch(address accounts, uint256 ids)→ Returns multiple token balances in a single call. -setApprovalForAll(address operator, bool approved)→ Grants or revokes permission for an operator to manage all your tokens. -isApprovedForAll(address account, address operator)→ Checks if an operator can manage all tokens of a specific account. -safeTransferFrom(address from, address to, uint256 id, uint256 amount, bytes data)→ Safely transfers a specific amount of one token type. -safeBatchTransferFrom(address from, address to, uint256 ids, uint256 amounts, bytes data)→ Safely transfers multiple token types in one transaction. Internal Functions _mint(address to, uint256 id, uint256 amount, bytes data) → Creates new tokens of a specific type. _mintBatch(address to, uint256[] ids, uint256 amounts, bytes data)→ Creates multiple token types at once. _burn(address from, uint256 id, uint256 amount)→ Destroys a specified amount of one token type. _burnBatch(address from, uint256[] ids, uint256 amounts) → Destroys multiple token types in a single transaction.