This blog post broadly examines the historical development of computers, from their origins to current technology, and explores the potential for future technological expansion.
A computer, by definition, is a machine that uses electronic circuits to automatically perform calculations or process data. However, this definition encompasses not only what we commonly refer to as a computer in modern society but also various other machines, and the boundary between computers and other machines is becoming increasingly blurred today. Therefore, this article will examine the definition of a computer, focusing on its history and components to distinguish it from other machines, and explore the types of computers classified by their intended use.
The mechanical calculator, considered the precursor to the computer, was invented by Blaise Pascal in the 1600s. Pascal’s calculator could only perform addition and subtraction, but later, Leibniz devised a machine capable of multiplication. In 1822, Charles Babbage designed the Difference Engine, capable of calculating polynomial, logarithmic, and trigonometric functions. By 1936, Alan Turing’s Turing machine emerged, applying the mathematical concepts of modern computers. Subsequently, German engineer Konrad Zuse developed a mechanical computer based on punched cards, and in 1946, the ENIAC, the first electronic computer using vacuum tubes, was born. In 1949, the EDSAC, developed by John von Neumann in the UK, appeared. This computer was the first to implement the stored-program concept and the binary number system. Subsequently, in 1952, the EDVAC was developed in the US. In 1951, the first commercial computer, the UNIVAC-I, was produced, marking the commercialization of computers.
With this successful commercialization, computer development accelerated rapidly. Early computers, like the ENIAC, used vacuum tubes, making them large, heavy, and slow, hindering widespread public use. However, the invention of the transistor at Bell Labs in 1947 sparked an electronic revolution, leading to the development of second-generation computers using transistors.
The IC (Integrated Circuit), invented in 1959, was used in third-generation computers, and operating systems (OS) emerged during this period. In the 1970s, LSI (Large Scale Integration) was invented, leading to the development of the microprocessor. Computers using microprocessors as their central processing units are classified as fourth-generation computers. It was at this time that IBM began using the term PC (Personal Computer). Subsequently, computers underwent remarkable development, with microchip data capacity doubling every 18 months according to Gordon Moore’s ‘Moore’s Law’.
Fifth-generation computers further enhanced performance using ultra-high-density integrated circuits. Furthermore, according to the ‘Memory New Growth Theory,’ the period for doubling semiconductor integration density shortened to one year, surpassing Moore’s Law. Consequently, the pace of semiconductor and computer development accelerates annually.
Beyond the fifth generation, computers are advancing into the field of artificial intelligence (AI). Although the development of artificial intelligence computers is currently in its early stages, considering that today’s computers were created just 70 years after the development of ENIAC, it is expected that artificial intelligence computers will also advance rapidly.
Along with the development of computers, their performance and functions have also changed in various ways. Early computers only had minimal input/output and computational functions for calculations, but modern computers possess much more diverse functions and characteristics, and will continue to change in the future.
The basic functions of a computer can be broadly categorized into five main functions. The components associated with each function are as follows.
The first function is input. To use a computer, the commands issued by the user must be transmitted into the computer’s internal system, requiring input devices. Keyboards, mice, and scanners are representative input devices. Digitizers that convert analog information to digital, microphones that convert sound to digital information, optical mark readers (OMR), optical character readers, and barcode readers are also used as input devices. Recently, biometric sensors that recognize fingerprints, irises, and veins, along with touchscreens, are also widely used as input devices.
The second function is memory. This function stores input data in the main memory. In the past, magnetic cores were used as main memory, but today, due to advances in semiconductor technology, RAM (volatile memory) and ROM (non-volatile memory) are used as main memory. Additionally, hard disks are widely used as secondary storage devices.
The third function is computational and control. The CPU (Central Processing Unit) handles performing calculations using programs or data stored in the main memory and controlling each device.
Finally, there is the output function, which displays the processed results through output devices. Early monitors used cathode ray tubes (CRTs), making them large and heavy, but the development of LCDs, PDPs, and LEDs led to the emergence of thin and lightweight monitors. Furthermore, touchscreens can perform both input and output functions simultaneously, blurring the distinction between them.
Thus, while computers possess certain core functions, their characteristics vary slightly depending on their intended use. The most widely known type is the personal computer (PC), used in homes, businesses, and schools. This category includes desktop computers, laptops, and tablet computers. Workstations are high-performance personal computers used in specialized fields such as engineering, design, and architecture.
Supercomputers are used for scientific and technological calculations, weather forecasting, and military purposes, characterized by ultra-high-speed computation and massive data processing capabilities. Supercomputers are not defined by specific criteria but refer to the fastest computers currently in use.
Beyond these, mainframes—large-scale computers—are used for processing massive datasets in areas like census data, statistics, and finance, primarily employed by government research institutions and large corporations.
In modern society, computers are used in nearly every field, and their pace of development is accelerating daily. Someday, computers possessing intelligence superior to humans may emerge.
