How did c4 get its name?

C4, or Composition C-4, derives its name from "Composition" and the letter "C," indicating it is the fourth in a series of similar explosives developed by the U.S. military. The "C" in its name refers to its chemical composition, while the "4" signifies that it is the fourth formulation in the series. C4 is primarily composed of RDX (cyclotrimethylenetrinitramine) mixed with plasticizers and other additives, making it a highly stable and effective explosive.