GIMP : Your Photoshop For Linux
If you are Linux fan and want to use PhotoShop on Linux then you have two options (i) Run Adobe PhotoShop in Linux via wine (ii) Use GIMP , alternative of Adobe Photoshop for Linux.
GIMP is a good graphics manipulation tool. This tool should help you get a taste of what GIMP is capable of.GIMP support lots of file format like TIFF, JPEG, PNG, GIF, PSD and some other like TGA, BMP, XWD, XPM, PIX, CEL, MNG, PPM and PCX. You may need extra plugins to support these file formats.
GIMP is not only for Linux user it also supports Windows , Mac OS X, BSD and Sun OpenSolaris.
If you need tutorials for GIMP then visit this site or you can read a book from here
Download GIMP For Linux
Ubuntu, Debian
Just run this command
apt-get install gimp
openSUSE
SUSE users can install GIMP by running yast –i gimp or zypper in gimp, depending on the distribution version.
Fedora
yum install gimp
Mandriva
urpmi gimp
For Windows and Mac OS X downloads click here