How do you change something to a compatible format like JPEG, GIF, or PNG?

Question

if it helps i have a apple desktop

Answer 1

Photoshop will allow you to change an image from one format to another simply by save as

Answer 2

There is no need for Photoshop, besides its way overpriced.

Paint.NET, Gimp, and/or IrfanView will be more then enough in most cases.

http://www.getpaint.net/

http://www.gimp.org/

http://www.irfanview.com/

All of the above are free. It would depend on which format you need to convert from, but the above should allow you to convert most formats.

You could also use iPhoto it comes with OS X as far as i know..