The G-48 is the fluted version of the standard Global Santoku Knife the G-46. A full sized Santoku, this knife can literally do anything, but is particularly will suited for chopping.
Fluting works really well with Santoku knives, as they typically are used for chopping vegetables and the fluting prevents starchy food such as potatoes from sticking to the blade as easily.
Santoku knives have become incredibly popular recently, but many brands actually produce with the fluting as standard on the assumption that it will be used as a vegetable chopper. Global do produce both.