There are two types of VST programs: VST instruments (a.k.a. VSTi) and VST effects. VST instruments produce sounds and VST effects change sounds. A synthesizer is a common example of a VST instrument. A reverb is a common VST effect.
Gating is often used by electronic music producers to chop up long, droning sounds into smaller, percussive bits of audio.
Next time your melody seems a little bland, throw in some tasteful vibrato to spice things up.