Cars over a certain age didn't have titles when they were originally bought. The Grandfather clause for those cars means they do not have to have Titles as the original owner of the car may still own it and decide to sell it. Those cars can be titled with a bill of sale and then registered with the title, or they can be simply registered without the title at all.

Cars 1986 and newer need titles. Cars between 63 and 85 do not need titles but can get them. Cars made in 62 or before do not get titles in the state of Georgia, and are simply registered/transfered via Bill of Sale.

Info here.

Google really could have answered your question as well as I did as far as the age of the car goes. I just happened to remember all of it from buying my 240z. Ed is spot on about the liens part as well. They won't issue you a new title unless the car has been de-registered and all liens on the car are signed for (Meaning the lien-holder has signed that he is ok with the car being sold/transferred).