Exploded view of a personal computer

The personal computer, 1970s – Like the lever and the abacus, it augmented human capabilities.

Personal computer – a general-purpose computer, whose size, capabilities, and original sale price makes it useful for individuals, and which is intended to be operated directly by an end-user.

Software applications for most personal computers include, but are not limited to, word processing, spreadsheets, databases, Web browsers and e-mail clients, digital media playback, games, and myriad personal productivity and special-purpose software applications. Modern personal computers often have connections to the Internet, allowing access to the World Wide Web.

hardware – power supply, motherboard, hard disk and often an optical disc drive. external devices – computer monitor or visual display unit, keyboard, and a pointing device, interface hardware, such as USB ports (previously parallel and serial ports), graphics card, sound channel,

  • QWERTY keyboard layout – designed to eliminate a mechanical problem with typewriter keys. The most commonly used letters would be as far apart as possible on the keyboard. He believed this would minimize the jamming problem.

Laptops contain high capacity batteries that can power the device for extensive periods of time, enhancing portability.
What’s the problem?
The Mother of All Demos – SRI researcher Douglas Engelbart in 1968 gave a preview of what would become the staples of daily working life in the 21st century – e-mail, hypertext, word processing, video conferencing, and the mouse. The demonstration required technical support staff and a mainframe time-sharing computer that were far too costly for individual business use at the time.

  • Ask – By 1968, big expensive computers were being used universities, government and companies. A few people like Doug Engelbart thought that there could be smaller, less expensive, easy-to-use computers for individuals.
  • Imagine – In his famous demonstration, Engelbart included e-mail, hypertext, word processing, video conferencing, and the mouse.
  • Design, Build – Although it took many years before all the hardware and software were available, eventually all these ideas have been developed for people to use with their personal computers.
  • Improve – There have been a continuous stream over improvements and new features added to personal computers. Electronics design and manufacturing improvements resulted in more powerful and less expensive computer components.

That’s engineering

  • central processing unit, or CPU, is that part of a computer which executes software program instructions. In newer PCs the CPU is about a million transistors in one integrated circuit chip called the microprocessor. The microprocessor plugs into the motherboard. The chip generates so much heat that the PC builder is required to attach a special cooling device to its surface. Modern CPUs are equipped with a fan attached via heat sink.
  • clock rate – the speed at which a microprocessor executes instructions. Every computer contains an internal clock that regulates the rate at which instructions are executed and synchronizes all the various computer components. The CPU requires a fixed number of clock ticks (or clock cycles) to execute each instruction. The faster the clock, the more instructions the CPU can execute per second.

Engineering ideas

  • software, client, network, interface, hardware, parallel, serial, graphics card, sound, high capacity battery

Do It
Challenges for you to work on…

  • find more information about the improvements of personal computers since the 1970s
  • label the components in the diagram above

Learn more…