The principle of the stored program
The principle of the stored program is considered the most important idea of computer architecture and, according to some scientists, the only one that caused the second industrial revolution in the second half of the 20th century. This idea is that, firstly, the computation program is entered in computer and stored in the same memory as the original numbers, and secondly, the commands that make up the program are represented in the form of a numeric code, they do not differ in form from the numbers, and with them you can perform the same operations, as with numbers.
The principle of the stored program, in addition, eliminates the need for physical modification of the computer whenever you need to execute a new program. In older computers with a dial-up program, the patching of the patch panel essentially resulted in a change in the physical structure of the machines. When you ran a new program, you had to change the panel wiring diagram. With the introduction of this principle, a new program is simply loaded into the computer's memory, and its execution begins with a specified memory cell. In addition, it becomes possible to keep more than one program ready for immediate execution. In the storage devices of the computer, various programs are stored, and the execution of any of them begins with the initial address of the desired program, as directed by the computer about the start of the run. This allows the computer to move from one program to another with electronic speed. This informs the computer flexibility and opens direct access to data, due to which the machine is adapted to solve a huge range of tasks and can very effectively perform complex calculations.
The question of who first put forward the principle of the stored program - until the end of the 1970s was decided unequivocally in favor of John von Neumann (1903-1957). This outstanding mathematician for the first time mentions the principle of a stored program in a report on the project of the EDVAC computer dated June 30, 1945. Then this ingenious idea is set forth in the article "Preliminary consideration of the logical design of an electronic computing device" written by Neiman in conjunction with A. Berks and G. Goldstein and received distribution in early 1946. Only thirty years later it became clear that, although Neumann played a significant role in introducing the principle of the stored program into practice, the principle was formulated before Neumann began to participate in the project.
The leaders of this project were J. Eckert and J. Mauchly, who in 1943-46 created the first American computer ENIAC (but not with the principle of the stored program). So, Mauchly then discovered a document dated January 1944, in which his former colleague Eckert expressed the idea of storing programs in computer memory. Mauchly announced that the idea was discussed by them in the process of designing the ENIACA, before Neiman, who first visited them in September next year. Another participant of the work, G. Hugheski, testified that when in the spring of 1944 he was invited to participate in the creation of ENIACA, Eckert told him about the principle of the stored program in memory.
