Beginner: what's the point of do files?

Hi everyone,

I know how to use STATA but there are few things which are quite obscure to me.
For example, I know it may sound silly but...what's the point of a do file?

I have read that it is a way of writing commands and even comments that can be easily executed once the software is ready.
However, what's the point? I mean, what I normally do is I type in the command and then I save them.

Can you please explain me what is the advantage of using these do files?
I would really appreciate it as they seem very important...

Again, apologize for this question...
Thanks very much!