Ic Case Study

3. Third Generation (1964-1975)

In 1958, Jack St. Clair Kilby and Robert Noyce invented the first integrated circuit. Integrated circuits (called ICs) are circuits consisting of several electronic components like transistors, resistors, and capacitors grown on a single chip of silicon eliminating wired interconnection between components. The IC technology was also known as “microelectronics” technology because it made it possible to integrate larger number of circuit components into very small (less than 5 mm square) surface of silicon, known as “chip” [see Figure 1.1 (c)]. Initially the integrated circuits contained only about ten to twenty components. This technology was named small scale integration (SSI). Later with the advancement in technology

In these systems, users had to prepare their data and programs and then submit them to a computer centre for processing. The operator at the computer centre collected these user jobs and fed them to a computer in batches at scheduled intervals. The respective uses then collected their job’s output from the computer centre. The inevitable delay resulting from this batch processing approach was very frustrating to some users, especially programmers. Because often they had to wait for days to locate and correct a few program errors. To rectify this situation, John Kemeny and Thomas Kurtz of Dartmouth College introduced the concept of timesharing operating system. Timesharing operating system enables multiple users to directly access and share computing resources simultaneously in a manner that each user feels that no one else is using the computer. This is accomplished by using a large number of independent, relatively low-speed, on-line terminals connected to the main computer simultaneously. Introduction of timesharing concept helped in drastically improving the productivity of programmers and made on-line systems feasible, resulting in new on-line applications like airline reservation systems, interactive query systems.

For example, several new operating systems were developed for PCs. Notable among these were MS-DOS, MS-Windows, and Apple’s propriety OS. Since PCs were for individuals who were not computer professionals. Companies developed graphical user interfaces for making computers more user friendly (easier to use). A graphical user interface (GUI) provides icons (pictures) and menus (list of choices) that users can select with a mouse. This enable new computer users to learn to use a PC quickly. Several new PC-based applications were also developed to make PCs a powerful tool. Notable among these were powerful word processing packages that allowed easy development of documents, spreadsheet package that allowed easy manipulation and analysis of data organized in columns and rows, and graphics packages that allowed easy drawing of pictures and diagrams. Another very useful concept that became popular during fourth-generations period was that of multiple windows on a single terminal screen. This feature allowed users to see the current state of several applications simultaneously in separate windows on same terminal screen. During fourth-generation period, UNIX operating system and C programming language also became very