How to write the introduction of a research paper?
Simon Peyton Jones has an excellent web page devoted not only to advice on writing introductions, but whole papers, and there is a cool video as well. On page 18 of his slides he says that the purpose of an introduction is to:

Describe the problem.
State your contributions.

He then goes on for a while to explain what precisely that means in pracrtice. But there is much more to his talk, I highly recommend it.
My personal piece of advice: never ever start your paper by saying &quot;In the recent years the foo technology has become important [1, 2, 3, 7, 10, 12, 13, 21] for saving the world peace, taking photos of kittens, and obtaining academic promotions. But all the people who did foo before us missed a minute point, which we are going to talk about at length in this paper. But first, let us bore you with a review of all the foos out there.&quot; Just get to the point, please.