Looping and closing browser

[smul...@yahoo.com]

I just downloaded the trial offer yesterday and I'm trying to figure
out the following scenarios:
1) Are there checkpoints to validate if a script worked?
2) Is there a way to use data driven looping...like to login with 3
different users all in a row?
3) How can I close the browser...

I'm new to this app and any help is appreciated!

Thanks