Giant Cracked was Cracked's first annual edition and lasted for 48 issues. It was completely published by Major Publications from 1965 to 1989.
For some bizarre reason, Cracked's first annuals were not advertised in the magazine, so readers who bought the regular issues and didn't look around, would have no idea that Cracked annuals were available for the first couple of years, which makes no sense business-wise. Hopefully they were placed next to the regular issues on the newsstands.