If you have a Windows computer, go to
All Programs →
gamside. If you don't see GAMS there, then you should reinstall GAMS. To open a local copy of the GAMS Model Library in the GAMS IDE goto
Model Library →
Open GAMS Model Library. Either press Enter or double-click the entry to open the file in the IDE; press F9 to run it.
If you want to run GAMS using the command line interface or are using a Unix or Unix-like operating system, you'll have two basic things that you can run from the command line:
gamslib <name> gams <name>
The first command will extract a model from the GAMS model library. You can also browse the model library at http://www.gams.com/modlib/modlib.htm.
The second command is how you run a GAMS program. Make sure that GAMS is in your path. If you open the command line window from within the GAMSIDE (click on the MSDOS button in the upper right corner), this will always be the case.