extracting script files

I've done a few maps in WE Trigger Editor. I want to learn a bit about native JASS though. How can I open the JASS file that stores what I did using Trigger Editor.

Thanks.

Extract "war3map.j" from the archive. You can do this with WinMPQ, MPQMaster, JassCraft or if you like command line utilities, Grimoire.

Thank you