Screen protectors are very cheap insurance against very expensive screen replacements. In general, there are two types, soft and hard. Soft ones are more glare resistant, while hard ones are more damage resistant. I recommend you get a 9H rated hard screen protector. Over time, the edges might get chipped, but those chips and other scratches would have otherwise killed your phone's screen.
I once slammed my trunk lid down on my iPad. I thought the screen was a goner, but when I removed the screen protector, the screen was in perfect condition. A few bucks for a new screen protector got my iPad back on the road.