system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is the use of a birth certificate?
gpt
It proves you were born here and are a citizen.   Without one, and without a record of one, they could try and deport you as an illegal immigrant. 

It also, you know, proves your age. For age-related things like getting into public school and getting a drivers license.