[Koayrbzh]

Nibbana meaning cooling off, the word comes from letting your pot stand for a while to cool down after cooking, you'd nibbana it for a while. Another metaphor for Nibbana is a candle flame going out, as has been pointed out this is the extinguishing of greed, aversion, and delusion.

Vipassana means clear seeing as has been pointed out, you don't need meditation for clear seeing to take place, however in it's modern usage Vipassana has come to mean a mode of meditation that is designed to promote clear seeing. Particularly clear seeing of impermanence, unsatisfactioriness, and not self which leads to release from greed, aversion, and delusion.

Jhana can also contribute to clear seeing but the trouble is you need to put aside a lot of time and be in condusive conditions with the right state of mind and the guidance of a teacher to make it work and not get caught up in it. This is why in modern times, for lay people at least, Vipassana oriented techniques or a Vipassana oriented approach are encouraged by most teachers.