Can someone give Lossless Music File 101?

I got little confused with different ways to make lossless music files and the names/types, and the tools, what is the actual file extension etc...

Is there a link that explains about the topic or can sombody here give some short lossless 101 lecture?

A few things I here a lot are 'Apple losslss', 'FLAC', 'Wave file', 'EAC', 'WMA lossless'

I get confused.