OM: Sacred monosyllable symbolizing oneness/the Absolute; the oldest, most popular mantra.
MANTRA: Thought or intention expressed in sound (e.g. prayer, hymn, plan).
MUDRA: Literally, a "seal" or way of "locking in" an intention, typically formed through hand gestures.
NAMASTE: "The light/divine within me bows to the light/divine within you," used as a greeting or farewell in India; traditionally said at the close of a yoga class.
ASANA: Used to refer to the postures we practice. Translates to mean "seat," as in a pose in which you are seated. While there are plenty of standing and supine positions, you should seek to feel grounded/rooted in all of them, as you would if you were seated.