Spade vs. banana plug

When I look at my banana plugs, the first thing that comes to mind is always bananas. A perfectly named connector.

@larryi

Spade, banana, pin tip plug or straight wire through post hole, and hooked wire around post

You pretty much got it, although bare wire whether through the hole or around the post count as one way.  The fifth is "double banana" plug.  The spacing between the red and black post is a standard distance, so a solid spacer could hold both banana jacks at the correct spacing to be inserted all at once (talk about the ultimate in lazy man convenience).