This guide is specifically for powerlifting bars for doing deadlift, [...]
So you want a good barbell, but you're conflicted as to what type to get.
The two main types of bars are power bars (also called powerlifting bars) and olympic weightlifting bars. Just so you know what we're referring to, weightlifting bars might also be called oly bars or olympic bars. Just to confuse things, "olympic bar" might mean anything. When someone says it, maybe they mean a weightlifting bar, or maybe they mean any bar with 2" diameter ends that will take olympic weights. Who knows. It depends on the context.