These first two titles (PRACTISE YOUR BASIC and PRACTISE YOUR CALCULATOR SKILLS) in this new series are packed with puzzles, problems, exercises, drills and games to help readers improve their skills. Each book takes the reader step-by-step through the basic principles of the subject with lots of fun and challenging problems to solve. In PRACTISE YOUR BASIC there are games and exercises to spot the bug and fill in missing variables and lots of puzzles to solve by writing programs. PRACTISE YOUR CALCULATOR SKILLS is packed with number games, missing numbers to spot and problems to solve with a calculator. All the answers, with detailed explanations, are given at the back of the book.