Bitcoin (and many other coins) are SHA256-based, meaning that all those hashing in bitcoin are sha256 hashing.

Litecoin (and many other coins) are scrypt-based, meaning that all those hashing in litecoin are scrypt-based.
Scrypt hashing is more memory intensive, and thus it is much harder to produce ASIC for it.

For CPU coins, it literally means the coin can only be mined using CPU (instead of GPU or ASIC).
Here is a list of CPU coins I find using google search. https://bitcointalk.org/index.php?topic=379601.0