What's the point of praying? [Spirituality & Religion]

[i]For those of you who are religious...[/i]Religious views depict God as all-knowing, so what difference does it make if you pray? Wouldn't he already know what's going on?

This post isn't meant to bash religious people (my whole family is religious) , so I'm not looking for negative replies. Just wondering about the mindset behind this. This is something they didn't ever really seem to explain lol