Giant robots saving the day in inventive sci-fi settings have been a staple of Japanese pop culture since its first appearance in anime and manga in the 1950s. To this day, the mecha genre is widely successful and adored by fans, as seen both in franchises that focus om giant robots, like Gundam and Zoids, and in mainstream anime with mecha elements, like Code Geass and Attack on Titan. The term “mecha” refers both to the genre and the robots themselves, which makes them the definitive component and focus of any mecha anime.
Source：https://www.cbr.com/strongest-mecha-robots/
