Type of Replacement Switch For Auto Dimming Outdoor Security Light
Exactly the switch you already have.

You look at your wiring -- and in doing so you ignore ground wires (which are green typically).  Ground is connected everywhere, but it doesn't participate in the normal wiring, so we don't talk about it.   If you see 


If the switch has 2 screws (again ignoring ground screws/wires), it's a plain switch.
If the switch has 2 brass and 1 black screw, it's a common 3-way.  
If the switch has 2 brass and 2 black screws, it's a 4-way middle switch. 
If the switch doesn't have screws but has pigtails instead, it's a dimmer, smart switch, motion sensor, that kind of thing. Snap us photos of anything distinctive and edit your post to include them.  


With 3/4 way switches, which screw is on brass vs. black is very important.  The physical position of the screws is useless and misleading (since every switch puts them in different places!!)  Also, wire color is useless and misleading - the screws they go to are the key.