Parallelizable manifold

A differentiable manifold M of dimension n is called parallelizable if there exist smooth vector fields

{V1,,Vn}

on the manifold, such that at every point p of M the tangent vectors

{V1(p),,Vn(p)}

provide a basis of the tangent space at p. Equivalently, the tangent bundle is a trivial bundle, so that the associated principal bundle of linear frames (the frame bundle) has a global section on M.

A particular choice of such a basis of vector fields on M is called a parallelization (or an absolute parallelism) of M. I think that this choice gives rise to a parallel transport and therefore to a covariant derivative operator (that I guess is flat since the holonomy is null)

Important examples: the Lie groups, and some of their homogeneous spaces (see this paper).