Bayonet Connectors: These are usually screw-on type connectors with a thin metal tip that sticks into a compatable speaker port on a receiver. You can usually tell receivers that use them because the port will have a small push button that slides a small hole open and closed.
Banana Plugs: These connectors resemble large bayonet connectors with the addition of little metal strips that expand outward similar to a light weight drywall screw. These plug into a small, uncovered round hole on each receiver speaker port. The hole is usually on the end of what resemble a large knob. In fact, these knobs can usually unscrew a bit to accept spade plugs, which are described below.
Spade Plugs: These are flat, horseshoe-shaped tips that fit around a screw which can be tightened down to hold everything in place. Spade plugs are usually crimped onto the ends of speaker wires.