Tangents are vectors in object space that are usually perpendicular to the normals. Binormals (which are also sometimes called bitangents) are usually perpendicular to both the tangents and the normals. In all common tangent spaces used today, tangent vectors correspond to pointing to the right on your UV map in 2D space.…
The "tangent" is vertex data. The "tangent space" is the basis formed by the normal, tangent, and bitangent vectors in which the normal map can pretend to always be pointing towards +Z. MikkTSpace is an algorithm that calculates a pretty good, standardized tangent space basis in a particular way, completely independent of…