What is the difference between CSS `position: relative`, `absolute`, `fixed`, and `sticky`?

Think of elements as people sitting in rows. A `relative` person slides their chair a bit without leaving their spot — the chair space is still 'reserved'. An `absolute` person gets up and hovers above everyone else, anchored to the nearest person who 'claimed their space' (a positioned ancestor). A `fixed` person floats and is nailed to a specific corner of the window — they don't move when you scroll. A `sticky` person sits normally until the row scrolls past a certain point, then they grab the window edge and stick there.