As video starts straight off with describing features of using "threads", I am left wondering: what is a "thread"? You are introducing new terminology without d

As video starts straight off with describing features of using "threads", I am left wondering: what is a "thread"? You are introducing new terminology without defining what it is. Give me a one liner at least. What problems does a "thread" solve? Don't list features, let me know what makes this different over email.