There are two ways. If you are on the internet, your ripper programme will connect to one of the CD databases, such as CDDB, and check the CD's unique code number- it's called the ISRC- and download the track list- even the cover art sometimes.
If there is no code number, what the database often does is look for a CD that has the same number of tracks of a similar length. So a CD that I use for a Student assignment- it's a reading of a short sci-fi story- comes up a a German version of Verdi's Aida!
About a third of the data on a CD is for other things than music. One of these is the ISRC, another is CD text-so that a good CD player will show you the artist, and song playing.   
Cheers
Dave