Who is transferFrom function sending tokens from?

Question

I'm new to Solidity and see:

function transferFrom(address from, address to, uint256 value)
    onlyOwner
    returns (bool)
{
  return super.transferFrom(from, to, value);
}

I mean is "from" here the contract address? Or can this be called by the owner to transfer from some address (given password) to any other address? Thank you!

Answer 1

Here's the basic flow for ERC-20. Assume Alice, Bob, Charlie.

1. Bob calls approve(Alice, 10).
2. Now Alice can call transferFrom(Bob, Charlie, 10).

Without Bob's approval, Alice's call to transferFrom will error out: she can't send Bob's tokens without his approval.

If Alice wanted to send to Charlie, she would instead call transfer(Charlie, 10) but that would send Alice's tokens.

from and to are any address (it can be a contract, but doesn't have to be).