on 10-30-2004 01:50 PM
An SDK, with reference to modelling and texturing, is a "Skin Development Kit" ... basically it's a resource, created by a modeller for the public to download.
An SDK usually contains a 3D model, and a bitmap image of the UV-mapping layout (also known as "maps" or "skinmesh").
Then, the artist doing the textures (sometimes referred to as "skins") can apply the image to the model, and digitally paint the texture.
So, usually an SDK is just a Zip file containing the models and all relevent image files.