Usborne were the book publishers that as a kid, were strangely distributed via school parents' front lounge.

I remember rarely being able to afford these books though they were, and are, rife with great educational material.

I've since bought a few of these for my own kids, the modern books that is, but this page also includes a full gamut of the computing books of the 80s - in particular BASIC and how to write a wide range of adventure games - for free, via PDF.

Usborne free book range

Really great stuff even to learn some fundamentals of how computers and software works.