Gpa question

Hi! I was looking around this sub and college admissions information in general and noticed that many people had a 4.0 uw gpa. I can't lie that I was suprised. My school considers us gpa as 97+ or an A+, so I always thought a 4.0 was impossible. Is this actually normal and people actually get 4.0 gpas this way? My uw gpa is 3.73 which is basically if I got a 95+ in every class. If this isn't the norm, then would the admission officers know how my school weighs gpa, or will they think I got Bs in every class? Any and all information would help! I'm kind of now to college apps so sorry if this is a stupid question.