Distance Learning implies some separation between learner and provider.    But it resists attempts at formal definition which might differentiate it from other forms of learning.

In practice, this does not matter much.    It is usually obvious when distance learning is involved.    Correspondence courses are distance learning; so is most online and e-learning.

School homework, on the other hand, which might be regarded as a form of distance learning, normally is not.    Perhaps this is because it is such a small part of school education, the rest of which is firmly face-to-face.

All this does not stop learned bodies trying to define distance learning.    Such definitions tend either to be short and impenetrable, place excessive emphasis on technology, or just ramble into a long and confusing essay.

Others avoid the problem by using or inventing different terms, like open, flexible, online or distributed learning, or home study.