A compliment usually given to a really cool girl by a guy. By pretty alright he actually means how cool she really is but the guy thinks it's best downplay her cool factor so he doesn't look "P" whooped in front of his friends when talking about her.
An expression or phrase used to describe something (or someone) that falls somewhere in between awesome and pretty good. Typically used in speaking very highly of something.
On a rating scale from 1 – 10, I would say she's pretty fuckin' alright.