Animation
From Second Life Wiki
An animation (anim) is a type of item in Second Life which animates an avatar (also by gesture). An avatar animation is typically created using Poser or an open-source program like Avimator or the more slightly more recent QAvimator (or any program that exports to BVH format--which SL only accepts at this time), uploaded to SL from the File Menu, and edited further in SL's animation preview window. A lot of built-in animations that can be used are found in the user's inventory.
Faces and hands can not be animated by the user, so residents must choose from pre-made face/hand positions provided by LL.
A pose is a single-frame animation. Pose stands are prevalent throughout SL and can change the avatar's pose from neutral (arms and legs out) to stand to sit to fly to just about anything else.
