Yes, it’s the place where you keep your brain and it usually sits on your neck. But the head we’re talking about here is the dedicated amplifier in a 2-piece amp/speaker cabinet setup. Fender built most of the early 2-piece systems, but other manufacturers quickly followed (heck, even Sears sold an amp/speaker combination in the 1960s). The most famous heads were those built by Marshall, and they remain a staple for rock supergroups. You probably couldn’t find a photo of Jimi Hendrix, Eric Clapton, or Pete Townshend on stage in the ’60s without that amazing backline of Marshall heads and stacked 4×12 cabinets.