Is safety glass used in all exterior home doors?

I locked myself out today, without keys, shoes, or cellphone, and with my oven on. None of my neighbors are home during the day, so I decided I had to get inside somehow. We have a back door with the top half of the door being glass with wood squares forming or simulating panes. I tried to break out one pane with a hammer and after beating on the glass with all my might for quite awhile it didn’t break. I was finally able to use a long flathead screwdriver between the door knob and frame and pop open the door (which is ok because we also have a dead bolt we can use). Now I’m wondering if all exterior doors have safety glass? This made me feel much better about break-ins considering I had such a horrible time breaking into my own home!