I have heard of them but have no idea on what they are, do any of you know? Thanks!

they're just image files, saved in Adobe Photoshop's proprietary format (so they preserve layers, things like that, as opposed to a more standard format that's widely used like jpg or png, which are mainly used when a lot of people are going to be viewing it, like on the Internet. but a format that is more customised to the program it belongs to is better for modifying the image)

psd's are often images that are cut out and saved like dude said in a psd format. Say if you want to make a layout from Britney for example, and you need an image that has no background. Then you search for a psd, that you can just insert in your layout without having to cut it out all the way around.

If you mean normal psd's, then dude's answer will do well. If you mean psd's like people often offer at their site's in this website world :P then it are images that have a transparent background.

Love,
Mirna

Ahh rite thank very much! :P

but what does psd stand for? can it only be made in adobe?

no you can save .psds in other programs like paint shop pro. I think it stands for like Photoshop Document or something (haha, it doesn't really matter, does it?)..it's just a type of file extension that saves the separate layers of your file.

coolie, thanx! :)