Are the eggs we eat fertilized?

Excuse me, but I'm curious about a topic that has been intriguing me for some time now. It's regarding the eggs we consume in our daily diets. Specifically, I'd like to know if the eggs we buy from the grocery store or eat in restaurants are actually fertilized? I understand that in nature, eggs are laid by hens after they've been fertilized by a rooster, but I'm not sure if this same process applies to the eggs we consume commercially. Could you please enlighten me on this matter?