Programming of Computers

The computer as described above is essentially just a calculator, and a very simple one at that. To be of any significant use in scientific problem solving, the computer must become programmable, in the sense that the sequence of calculations and decision making criteria to direct the calculations can be set out and made to control the sequence of steps taken by the calculator. The set of instructions which describe the process is called a program, and any programmable computer must have circuitry to allow it to execute the instruction sequence described in such a program. At the lowest level, the program is written in machine code, which is in a format appropriate for direct interpretation by the computer circuitry as the computer reads the instruction sequence from some source, such as the computer's memory. This language level is very far from any human language, and thus quite inappropriate for the description of the methods to solve scientific problems.