The 80-Page Giants were DC's first attempt to collect previously published material and sell it to consumers. The early issues were called "Annuals" even though Superman and Batman Annuals appeared semi-annually. These Annuals contained 80 squarebound pages plus covers and were sold for 25¢.

In 1964, after successfully publishing 22 of these Annuals, DC decided to create an ongoing "Giant" series to make distribution easier. The decision must have come at the last minute because "80 Page Giant #1" was shown as Superman Annual #9 in house ads and the new 80pg. Giant cover logo was clearly pasted on top of the old "Giant" logo.

After publishing 15 monthly issues of 80 Page Giant, DC decided to discard the umbrella title. The giants were instead rolled into their parent titles and numbered as regular issues of those titles. JLA #39 was the first of these giants. The "G" numbering system was used on the covers to denote it as a giant. 89 issues were published in the "G" series. The series kept a monthly schedule with one extra Batman issue (#G-27) appearing. The extra issue was likely released to capitalize on the Batman TV show.

One unlettered 64 page giant, Young Love #69, was also published in 1968. Likely it was a prototype for DC Special, though it had the "Giant" logo associated with Series "G".

In 1969 rising production costs caused DC to hike prices from 12¢ to 15¢. Giants stayed at the standard 25¢, but were reduced from 80 to 64 pages plus covers. Action #373 (aka G-57) was the first 64-page Giant from Series "G". Beginning with Justice League #85 (aka G-77), the binding of Series G switched from squarebound to saddle-stitched.

In 1971 DC switched formats again, increasing page counts on all standard comics from 32 to 48 and raising the price from 15¢ to 25¢. By this point DC was ready to abandon the 64-Page Giant format and start again with a new giant format, 100-Page Spectaculars. The final four issues of series "G" got caught in between formats and ended up with a 35¢ cover price.