Goa is the name of a sub-genre of Trance that has roots all the way back to the province of Goa in India. It is characterized by its use of a driving
4/4 beat (some
goa is in
3/3), a trance-inducing melody(usually in an eastern or indian set of notes a.k.a. scale) that is performed by various synthesizers (not all of it is done with a roland
TB-303, God, that would be boring as hell), and various effects like teleport
zapping, blasts, and pitch bending cracks that help to create a mystical like state to a listener. Lastly, goa is TRANCE, not techno. Duh. Oh yeah, and
psytrance is just a broken down more mechanical version of goa, if you were wondering.