Simple ERC20 Token

See {IERC20-allowance}.

See {IERC20-approve}. NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on `transferFrom`. This is semantically equivalent to an infinite approval. Requirements: - `spender` cannot be the zero address.

See {IERC20-balanceOf}.

Returns the number of decimals used to get its user representation. For example, if `decimals` equals `2`, a balance of `505` tokens should be displayed to a user as `5.05` (`505 / 10 ** 2`). Tokens usually opt for a value of 18, imitating the relationship between Ether and Wei. This is the value {ERC20} uses, unless this function is overridden; NOTE: This information is only used for _display_ purposes: it in no way affects any of the arithmetic of the contract, including {IERC20-balanceOf} and {IERC20-transfer}.

Atomically decreases the allowance granted to `spender` by the caller. This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}. Emits an {Approval} event indicating the updated allowance. Requirements: - `spender` cannot be the zero address. - `spender` must have allowance for the caller of at least `subtractedValue`.

Atomically increases the allowance granted to `spender` by the caller. This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}. Emits an {Approval} event indicating the updated allowance. Requirements: - `spender` cannot be the zero address.

Returns the name of the token.

Returns the symbol of the token, usually a shorter version of the name.

See {IERC20-totalSupply}.

See {IERC20-transfer}. Requirements: - `to` cannot be the zero address. - the caller must have a balance of at least `amount`.

See {IERC20-transferFrom}. Emits an {Approval} event indicating the updated allowance. This is not required by the EIP. See the note at the beginning of {ERC20}. NOTE: Does not update the allowance if the current allowance is the maximum `uint256`. Requirements: - `from` and `to` cannot be the zero address. - `from` must have a balance of at least `amount`. - the caller must have allowance for ``from``'s tokens of at least `amount`.