Transparent means people can tell how much money you have, how long you've had it, where you got it from, and where you send it. An opaque chain means outside

Transparent means people can tell how much money you have, how long you've had it, where you got it from, and where you send it. An opaque chain means outside observers can't really do that. If people have the private key, of course they can, or if they have view keys they can. The the chain is verifiable even while being opaque thanks to the beauty of mathematics.