How do you use PAT files in Photoshop?

I download pat files from say Deviantart and there are supposed to be many files on this one PAT file but I dont see anything. I have quite a few of these files now and Im about ready to just delete them. I would like to know how to see them and retrieve them from this main PAT file though. Any ideas?

To load patterns, use the Preset Manager. (Edit -> Preset Manager) Once a pattern collection has been loaded, it will then be available to all tools that use patterns (Paint Bucket, layer blending effects, etc.).

OH thank you, thank you! The tutorials I had tried to use had me opening alpha channels and the other layers and I just wasnt getting it right. This is WONDERFUL! Thanks again so much!!

Since you are so knowledgeable I want to ask you if you know what a postScript file is and how to use it. I tried to use them but Photoshop wont open them up.

I'm sure some of the programmers in the crowd could provide a more thorough explantaion than I, but basically, postscript is a programming convention for describing page layouts. It will typically include vector-based instructions for imagery, text, relative scalings and object locations, etc. It's primarily used for printing purposes.

See http://www.adobetutorialz.com/articles/207/1/What-is-PostScript%3F for more information.

If you want to view a postscript file, you can do so in a dedicated scripting program like Ghostscript, or you can convert it to a PDF with Acrobat Professional. Adobe Reader might be able to open one, but I'm not sure. I've had the full version of Acrobat on every computer I've had for several years now, so I really don't use Reader.

There's also what's called encapsulated postscript (EPS), a file format which can contain both vector and raster data at the same time. It can be read by nearly all graphics and page layout programs, including Photoshop. Note, vector objects will be rasterized when an EPS file is opened bu any non-vector-based program, again including Photoshop.