zeppelin-solidity/contracts/token/TokenVesting.sol

In following release function parameter "ERC20Basic token", i dont understand the this parameter , plz help em out .

function release(ERC20Basic token) public {
uint256 unreleased = releasableAmount(token);

require(unreleased > 0);

released[token] = released[token].add(unreleased);

token.safeTransfer(beneficiary, unreleased);

Released(unreleased);

}

You're using a very old version of OpenZeppelin Contracts. See our policy on supported versions.

TokenVesting was removed a while ago though, but is being added again next release.