I can honestly say I learned how to program by reading these books.  A simply fantastic series of books.  Appearing childish at first with their cute little cartoon robots and such, they provide a solid, well-explained introduction to BASIC and machine code programming on 8-bit systems.  They support just about all 8-bit systems and most programs worked with 1K of memory! (anyone remember the ZX81?)  The games were the type-them-in-yourself sort, and were often well worth the trouble.  I've never seen a better set of programming books.  Short, and to the point.  Bigger is not always better.

At Usborne's request, the PDFs of their books have been removed from the museum. However, they have kindly provided their own PDFs of the entire series now at no charge, and these can be found here.