This scientific article speaks about generations of computers, PC history, saving data, Von Neumann architecture, input/output peripherals, software instructions, programs, mainframe, minicomputers, microcomputers, supercomputers, libraries and operating systems, computer networks and Internet, introduction to the world of computers, evolution of computer systems, from the literature specialized in computer science. Computers are divided into: mechanical computers-water and gas meters, electromechanical computers-electricity meters, electronic computers (I generation of computers, II generation of computers, III generation of computers, IV generation of computers), optical computers and biological computers. After the highest prevalence, electronic computers are divided into: analogue-electronic computers, digital electronic-computers and hybrid electronic computers.
Keywords: Computers, Mainframe, Microcomputers, Minicomputers, Operating Systems;, Supercomputers
