A primitive, or prim, is the basic building block for objects in Second Life. Larger and more complex objects can be created by linking multiple prims together.
Background
In Second Life, virtual physical objects such as aircraft, houses, jewellery, and even less obvious things like hair and clothing, are made out of one or more prims. Objects made from prims are usually created in-world using the built-in object editing tool.
Each prim is represented by a set of parameters, including shape/type, position, scale/size, rotation, cut, hollow, twist, shear, etc. The color, texture, bumpiness, shininess, and transparency of prims can also be adjusted, and images (textures) can be applied to each surface (face/side) of a prim to change its appearance. Box, cylinder, and prism prim shape types can also be made flexible.