What does a operating system update actually do? What are the affects?

Thanks

I know what an operating system is, but what does it to when you update it? For example, does it increase battery life, increase reception, etc...?

What operating system update are you referring to? Each one does something different, and RIM rarely posts a changelog for each update.

There's no canned answer for the questions you're asking.

Best answer to your question is to tell you to ring the strings for each upgrade (sticky at top of forum) and see what the users are reporting as they upgrade.

Some people advise that if you are having no problems, especially if you are in any way uncomforatable or unsure about the upgrade, to leave it alone.

(Others of us upgrade as soon as a new OS is posted.)