> For the complete documentation index, see [llms.txt](https://otherworld-1.gitbook.io/protocol-1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://otherworld-1.gitbook.io/protocol-1/smart-contracts/oklay-erc-20-contract.md).
# oKLAY(ERC-20) Contract
## Address
> Address : (not yet deployed)
>
> on Klaytn Blockchain Main-net
## 개요
> **The oKLAY contract defines FT with a value that corresponds 1:1 to KLAY.**
* Defines the 'name'.
* Define the 'symbol'.
* Issues 'FT'.
* Defines the token quantity.
* The token balance of the deposit account will increase by the amount of KLAY deposited in the oKLAY contract.
* oKLAY can be withdrawn as KLAY.
* The total capacity of oKLAY is equal to the KLAY balance deposited in the oKLAY contract.
## Data
### Base
Name
Type
Name
String
Symbol
String
### FT
Name
Type
Owner
Address
Balance
Uint
## Event
### Transfer
Name
Type
From
Address
To
Address
Value
Uint
### Approval
Name
Type
Owner
Address
Spender
Address
Value
Uint
### Deposit
Name
Type
From
Address
Value
Uint
### Withdrawal
Name
Type
To
Address
Value
Uint
## Interface
{% tabs %}
{% tab title="IOWOtherKlay" %}
```solidity
interface IOWOtherKlay {
function deposit() external payable;
function withdraw(uint256 amount) external;
}
```
{% endtab %}
{% tab title="IERC20Metadata" %}
```solidity
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
```
{% endtab %}
{% tab title="IERC20" %}
```solidity
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 amount
) external returns (bool);
} /**interface IERC20Metadata is IERC20 {interface IERC20Metadata is IERC20 {
```
{% endtab %}
{% tab title="IERC165" %}
```solidity
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
```
{% endtab %}
{% endtabs %}