Fifteen years ago one could purchase a hand operated calculator which, by much lever pulling and handle twirling, performed the four basic arithmetical operations. Such a calculator cost around £40. Today electronic programmable calculators can be bought for prices which are less, in real terms, than that of the old mechanical calculator. As will be illustrated by examples later, such calculators incorporate the major features of a full-scale computer, and by constructing programs for a hand-held electronic calculator one can learn the basic tactics and strategies of computer programming. There are definite advantages in starting programming with a hand-held calculator; it is inexpensive, much of the ‘language’ will be familiar because hand-held calculators are now so commonly used, and one can test and use programs immediately they are written.