By Mobina Ahmed

Computer Hardware

Hard drive (HDD/SSD)

What is a HDD?HDD stands for hard disk drives, a hard disk drive is the main part of the computer which helps stores all your data. The HDD can hold over 100 GB (gigabytes) of data. all your data will be saved onto the computer even when it is turned off.What is a SSD?SSD stands for solid state drive, it is also known as a flash drive the SSD is different from the HDD because it has no moving parts and uses a special kind of memory chip.

Optical Drive

When you have cd's and dvd's the optical drive has lasers which help the computer understand what is going on the cd or dvd. Some common types of optical drives include CD-ROM, CD-RW, DVD-ROM, DVD-RW, and Blu-ray drives. CD and DVD writers, such as CD-R and DVD-R drives use a laser to both read and write data on the discs.

Computer Monitor

A computer monitor is an electronic device which shows pictures  Monitors often look similar to televisions. The main difference between a monitor and a television is that a monitor does not have a television tuner to change channels. a computer monitor is defined as a display output hardware of a computer, a machine code monitor s a programming device that enables users to view and change memory locations on a computer. 

Input devices and Output devices

 Before a computer can process your data, you need some method to input the data into the machine. The device you use will depend on what form this data takes (be it text, sound, artwork, etc.). Similarly, after the computer has processed your data, you often need to produce output of the results. This output could be a display on the computer screen, hardcopy on printed pages, or even the audio playback of music you composed on the computer. The terms “input” and “output” are used both as verbs to describe the process of entering or displaying the data, and as nouns referring to the data itself entered into or displayed by the computer.input devices are:keyboard , mouse microphone, scanner, trackball,headphones, output devices are:computer monitors, speakers

Touch screens

A touchscreen is an electronic visual display that the user can control through simple or multi-touch gestures by touching the screen with one or more fingers. Some touchscreens can also detect objects such as a stylus or ordinary or specially coated gloves. The user can use the touchscreen to react to what is displayed and to control how it is displayed (for example by zooming the text size).The touchscreen enables the user to interact directly with what is displayed, rather than using a mouse, touchpad, or any other intermediate device (other than a stylus, which is optional for most modern touchscreens).Touchscreens are common in devices such as game consoles,all in one computers, tablet computers, and smartphones. They can also be attached to computers or, as terminals, to networks. They also play a prominent role in the design of digital appliances such as personal digital assistants(PDAs), satellite navigations devices, mobile phones , and video games and some books.The popularity of smartphones, tablets, and many types of information aplliances is driving the demand and acceptance of common touchscreens for portable and functional electronics.


When shopping for motherboards for a PC, two of the most important specifications are the CPU and the RAM. Both of these elements affect how fast your computer runs, but in very different ways, as they have very different functions. In order to get the most performance out of your computer, it’s best to understand the roles CPU and RAM play in your PC’s overall speed.What is CPU?: CPU stands for Central Processing Unit. The CPU is the brains of your computer. It processes all the mathematical calculations required to make programs run. The speed of your CPU is measured in hertz (scaling up to megahertz and gigahertz), or how many cycles it can process per second. When your computer runs programs, it’s essentially following a set of instructions one at a time. CPUs can have multiple cores (i.e. dual-core or quad-core), which allows it to perform several processes at once. In a way, it’s a bit like the checkout line at the grocery store—adding a core is like opening an additional register, allowing the CPU to process instructions twice as fast.Whar is RAM?: RAM stands for Random Access Memory. This is a different kind of memory that is used to store files permanently on your hard drive. Rather, RAM could be considered short term memory. The data stored in your RAM is the information that is necessary to keep a program running or complete a process. Think of it a bit like the work space for a math problem where you work out the smaller calculations that help you determine the solution to the entire problem. To this end, RAM is incredibly important to multitasking (i.e. running multiple programs at once). RAM allows a program to continue running in the background so you can return to it without re-launching it.

Tim Berners-Lee

Tim Berners-Lee: A graduate of Oxford University, Tim Berners-Lee invented the World Wide Web, an internet-based hypermedia initiative for global information sharing while at CERN, the European Particle Physics Laboratory, in 1989. He wrote the first web client and server in 1990. His specifications of URIs, HTTP and HTML were refined as Web technology spread.In 2001 he became a Fellow of the Royal Society. He has been the recipient of several international awards including the Japan Prize, the Prince of Asturias Foundation Prize, the Millennium Technology Prize and Germany's Die Quadriga award. In 2004 he was knighted by H.M. Queen Elizabeth and in 2007 he was awarded the Order of Merit. In 2009 he was elected a foreign associate of the National Academy of Sciences. He is the author of "weaving the web".

Alan Turing

From November 1942 until March 1943 Turing was in the United States liaising over decoding issues and also on a speech secrecy system. Changes in the way the Germans encoded their messages had meant that Bletchley lost the ability to decode the messages. Turing was not directly involved with the successful breaking of these more complex codes, but his ideas proved of the greatest importance in this work. Turing was awarded the O.B.E. in 1945 for his vital contribution to the war effort. At the end of the war Turing was invited by the National Physical Laboratory in London to design a computer. His report proposing the Automatic Computing Engine (ACE) was submitted in March 1946. Turing's design was at that point an original detailed design and prospectus for a computer in the modern sense. The size of storage he planned for the ACE was regarded by most who considered the report as hopelessly over-ambitious and there were delays in the project being approved. Turing returned to Cambridge for the academic year 1947-48 where his interests ranged over many topics far removed from computers or mathematics; in particular he studied neurology and physiology. He did not forget about computers during this period, however, and he wrote code for programming computers. He had interests outside the academic world too, having taken up athletics seriously after the end of the war. He was a member of Walton Athletic Club winning their 3 mile and 10 mile championship in record time. He ran in the A.A.A. Marathon in 1947 and was placed fifth.

The 4 generations of computers

The British Colossus was the first ever programmable digital computer. This top secret computer came into service at the end of 1943 and was developed to break German telex traffic, encrypted with the Lorenz SZ40/42 machines. Although Colossus operated two years earlier than the publicly well known American ENIAC, it never received the proper credit due to its top secret status during and after the war. It was only in the late 1970's that information about this wonderful machine became available. Unfortunately, this magnificent machine is hardly mentioned in history books.
Over 200 Elliott 803 computers were delivered to customers, at a price of about £29,000 in 1960 in 2010 two complete elliott 803 survived one is owned by the science museum in london but it is not on display for public the other one is in the national museum of computing at bletchley park and is fully functional. Both machines are the subject of a computer conservation society restoration and maintenance project which currently concentrates on the machine at TNMoC. Consequently this machine can regularly be seen in operation by visitors to that museum. An incomplete third elliott 803 was found decaying in a scrap yard. Where possible, parts were removed for use as a source of spares for the machine at TNMoC.
ICs were made possible by experimental discoveries showing that semiconductor devices could perform the functions of vaccum tubes and by mid 20th century technology advancements in semiconductor device fabrication. The intergration of large numbers of tiny transistors into a small chip was an enormous improvement over the manual assembly of circuits using discrete electronic componenets. The integrated circuit's mass production capability, reliability and building block approach to circuit design ensured the rapid adoption of standardized of integrated circuits in place of designs using discrete transistors.
The BBC Micro computer system. or BBC Micro was a series of micro computers and associated peripherals design and built by the Acorn Computer company for the BBC computer literacy project operated by the british broadcasting corporation. Designed with an emphasis on education, it was notable for its ruggedness, expandability and the quality of its operating system. It was also moderately successful as a home computer in the UK despite its high cost. Acorn also employed the machine to simulate and develop the ARM architecture which is much used for embedded systems.

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