The YCash is a new cryptocurrency made on the ZCash software. The YCash fork happened at block height 570,000 of the ZCash blockchain, which means that everyone in control of Zcash private keys as of block height 570,000 are able to use those private keys to access the same amount of Ycash.
Its total supply is forever capped at 21,000,000 coins, which means you never have to worry about inflation, devaluing your Ycash, in contrast with government-issued paper cash. Other distinguished features of the new blockchain will be:
To receive the YCash, just hold your ZCash in Atomic Wallet on July 18.
More information can be found on the Ycash official website.