The third generation of computers, from 1965 to 1971, used Integrated Circuits (ICs) instead of transistors. An IC is a small chip that contains many transistors, resistors, capacitors, and the necessary connections all in one piece, making computers smaller and more efficient. This invention, by Jack Kilby, made computers more reliable and faster. During this time, new systems like remote processing, time-sharing, and multiprogramming were introduced to help computers work more efficiently.

Third Generation of Computer
The Third-generation computers reduce Third-generation time. In the previous generation, the computational time was microsecond, which was decreased to the nanosecond. In this generation, punch cards were replaced by the mouse and keyboard. Also, multiprogramming operating systems, time-sharing, and remote processing were introduced in this generation. BASIC, PASCAL, ALGOL-68, COBOL, and FORTRAN-II third-generation computers.
During the third generation, the computer has a larger storage capacity than the previous generations. These computers have magnetic storage. Some examples of third generation computers are IBM 370, PDP-11, IBM System/360, UNIVAC 1108, Honeywell-6000, DEC series, and ICL 2900.
Characteristics of Third-Generation Computers
Third-generation computers were faster, more reliable, compact, used ICs, supported high-level languages, and had improved storage and input devices. Here is the characteristics table for the third generation of computers:
| Characteristic | Description |
|---|---|
| Performance and Efficiency | Third-generation computers were faster, more efficient, and delivered better performance with less power usage. |
| High-Level Programming Languages | Introduced languages such as BASIC, PASCAL, ALGOL-68, COBOL, FORTRAN II, and PL/I, making programming more versatile and user-friendly. |
| Input Devices | Replaced punch cards with keyboards and mice, improving user interaction and ease of use. |
| Integrated Circuit (IC) Technology | Replaced individual transistors with integrated circuits, reducing size, improving reliability, and increasing speed. |
| Storage Capacity | Features significantly higher storage capacities, allowing for the efficient processing and storing of more data. |
| Size and Cost | More compact and affordable compared to previous generations, making them accessible to a broader range of businesses and organisations. |
Advantages of Third-Generation Computers
Third-generation computers were compact, energy-efficient, reliable, user-friendly, had high storage, and offered improved speed and portability.
- Compact and Space-Efficient: Integrated Circuits (ICs) reduced the size of computers, combining multiple components on a single silicon chip.
- Energy Efficient: Lower power consumption and heat generation led to more efficient operation and fewer cooling requirements.
- Improved Reliability: ICs offered better durability, reducing hardware failures compared to earlier generations.
- User-Friendly Input: Replaced punch cards with keyboards and mice, making computers more accessible and easier to operate.
- High Storage and Accuracy: Increased storage capacity and more accurate computations made complex data processing easier.
- Portability and Speed: Smaller size and improved speed made these computers more portable and faster than previous models.
Disadvantages of Third Generation Computers
Third-generation computers required air conditioning, had complex IC manufacturing, difficult maintenance, high initial cost, limited software compatibility, and needed a skilled workforce.
- Air Conditioning Needed: Despite energy efficiency, large systems still require air conditioning to prevent overheating.
- Complex IC Manufacturing: Producing Integrated Circuits was costly and required sophisticated, precise technology.
- Difficult Maintenance: Repairing or replacing malfunctioning ICs was complex due to their small size and intricate design.
- High Cost of Initial Setup: Although more affordable than earlier models, the initial cost of third-generation computers and their infrastructure remained high.
- Limited Software Compatibility: The shift to new technologies sometimes led to compatibility issues with older software, requiring updates or complete replacements.
- Skilled Workforce Requirement: Operating and maintaining these advanced systems required specialised knowledge, creating a need for a more skilled workforce.
First vs Second vsThird Generation Comparison
Here is the comparison table for First, Second, and Third Generation Computers:
| Aspect | First Generation (1940s-1950s) | Second Generation (1950s-1960s) | Third Generation (1960s-1970s) |
|---|---|---|---|
| Technology | Vacuum Tubes | Transistors | Integrated Circuits (ICs) |
| Size | Large and bulky | Smaller, still bulky | Compact and space-efficient |
| Speed | Slow | Faster than the first generation | Faster with improved processing power |
| Input Devices | Punch Cards | Punch Cards, some keyboards | Keyboards, Mouse |
| Output Devices | Printers, Punch Cards | Printers, Monitors | Monitors, Printers |
| Power Consumption | High | Lower than the first generation | Much lower compared to previous generations |
| Cooling Requirement | Extensive air conditioning | Reduced cooling needs | Reduced, but still required cooling for large systems |
| Reliability | Prone to frequent failures due to vacuum tubes | More reliable than the first generation due to transistors | High reliability with fewer hardware failures |
| Programming | Machine language | Assembly language, early high-level languages like COBOL | High-level languages like COBOL, FORTRAN, BASIC |
| Cost | Very expensive | More affordable than the first generation | More affordable and efficient |
| Applications | Calculations, military use, and basic research | Business applications, scientific computing, and early automation | Commercial and scientific applications, business automation |
Conclusion
The third generation of computers, from 1965 to 1971, introduced Integrated Circuits (ICs), making computers smaller, faster, and more reliable. With the use of high-level programming languages like COBOL and FORTRAN, computers became easier to use. They were more affordable than earlier models, but still required skilled maintenance. This generation helped shape modern computing and improved how businesses and scientists used computers.