ERC-20 Token

1 [basic]
A token on the Ethereum network which implements all the API's defined in ERC-20. The ERC-20 describes the minimal API all tokens are recommend to follow.
2 [medium]
A token which implements the ERC-20 API. The token contract must implement the following methods.
totalSupply() - Get total token supply
balanceOf(owner) - Get address balance
transfer(to, value) - Transfer some amount to an address
transferFrom(from, to, value) - Send the value from an address to another
approve(spender, value) - Authorize the spender to spend up to the value amount
allowance(owner, spender) - Get amount still approved for withrawal

Transfer(from, to, value) - When tokens are transferred
Approval(owner, spender, value) - When approve is called