What is teaching?

So what does the term teaching or teacher mean to you?
Teaching to me is about providing relevant and useful information to anyone that requires this knowledge. It may be formal as in school where there is an expectation of what is to be taught, or informally in real life where someone needs to know something that you know.

What is the difference between a teacher and a learning manager? Is there a difference?
No difference as far as I am concerned, both the learning manger and the teacher provide information to who ever requires it.