What type of Light Switch is this, a 2 or 3 way. Need to replace switch.
Three terminals (the screws) indicates a 3-way switch. If there is a terminal on the unseen side, then it is a 3-way switch. Also, there should be a red wire if it is 3-way. I also can't see inside the box. Does this switch control two light fixtures? Is that why there are three black wires? This switch may not be wired correctly.
This switch only controls one light in closet.
Can't tell from the picture. Does this switch turn a light on and off with another switch? If it does it's a three way. If not it's a standard switch. It also looks like it's not wired properly.
This switch only turns on my closet light.
My husband took electricity in the army (is not certified but does all our electrical needs) and he says it is a 3 way
Then it's just a standard switch. Three way switches can't be connected to operate only one fixture.
The third wire connected to the switch is a mystery. It looks like you have power coming into the box (one black) and then power to the light fixture (second black). Even if this box powered another receptacle or device, that black would be wire nutted in the box, not connected to the switch unless the switch was meant to control something else. I am assuming the neutrals (white wires) are in the box and we just can't see them. Another way to tell if it is a 3-way switch is there are no "On" or "Off" markings.
I think the third wire feeds power to other switches or outlets creating a loop. Instead of having wire nutted a pigtail for the switch they connected directly to the switch. Not a general practice.
That would make sense. Craig, if you have not rewired the new switch yet, don't do it the way it was by backstabbing that third black wire. Wire nut the two hot black wires and pigtail them to the screw terminal. When you shut the breaker off to change the switch, figure out what else is on that circuit and what that third wire might go to. Make sure it is accurately recorded on your panel schedule.