The mecha subgenre has always seemed oddly specific and I've wondered at the its development for some time. What about the inclusion of 'mechs separates this genre from other science fiction? A brief discussion of the history of mecha anime/manga would likely be worthwhile, but also some looks at outliers in the genre, such as Gurren Lagen with its strange mecha design and early disinterest in mechas, or creations that stick mechas in largely non-science-fiction terms. Basically, though, the question is "why does adding giant robots make this genre something special and unique?"
