In
animation, the process of creating a single animation curve for
an object whose actions are being provided by simulation rather
than by keys and animation curves (keysets). This
process makes many types of animation available that are not available
for keyset editing.
In
rendering, the process of rendering illumination, shadow, shading,
and textures to a file texture or to per-vertex color mesh. Baking
lets you render an object once and either re-use the file texture
as a texture map or bake colors onto vertex meshes. Texture maps
can also be manipulated to obtain lighting effects that would be
difficult to achieve in other ways.
In mental ray for Maya, also known as light
mapping.