Those are chain split forks. They fork from the Bitcoin blockchain directly at a specific block number. This gives the holder at the block number claimable coins. "free coins"

Litecoin,Dash and many others are code forks. They fork the codebase of the chain ie Bitcoin.

Chain split forks are either due to politics(Bcash) or a way to airdrop coins in a decentralized way(bootstrapping holders)