Although most microcomputers are programmed in Basic, the machine itself can only understand so-called 'machine code', a much more primitive language. Programming in Basic is generally much easier, but the necessity of bridging the gap between Basic and machine code, which is what the Electron's Basic interpreter does, tends to make programs written in Basic both long and relatively slow.

Programs that are written directly in machine code are much more compact, and much faster. This is how the best of the action games are written, so there are advantages to writing programs in machine code, though it is harder. Such programs are normally written in a slightly easier format called Assembler and this book provides a comprehensive introduction to this form of programming.

Assembler programming is not an easily learnt skill and most books on the subject take a fairly format approach. The book reviewed here attempts a more popular approach with a number of somewhat gimmicky diagrams and illustrations that unfortunately tend to confuse rather than clarify the ideas being presented.

The order of presentation is also somewhat unusual with reference to subroutines and stacks before more than the most elementary addressing modes. Many aspects of assembler programming are covered including, for example, more advanced topics such as interrupts. There is also quite good coverage of the ways in which assembly language programs are embedded within Basic on the Electron.

This books represents an honest and worthwhile attempt to popularise what can often be a difficult subject. Unfortunately, this is not altogether successful in this case, and I continue to believe that a more serious approach is still the best for this subject. That apart, this is a sound book that will help many users to learn assembly language programming, and is reasonably priced.