The address you sent me is invalid, are you sure you copied it correctly?

You can read more about the coin at this website: https://raiblocks.net/, or on its subreddit. There is some "PoW" involved but it's used to deter spammers, and it's not a key component of the protocol. Since there are no fees, there's no tangible economic disincentive to deter someone from spamming the network. Thus, before sending a transaction you have to solve a small problem that takes a couple of seconds in commodity hardware.