The file has been modified from the myetherwallet.com wallet and classicetherwallet.com for those of us that want to exclusively use Etc without having to install a full node . Its a great tool ,with many useful features and will definitely make it alot easier to spread Etc around ,hopefully growing the community .
You can read more about the features here at ClassicEtherWallet
and you can grab the Chrome extension here Google Webstore
and start using your Eth Classic wallet straight away .