CSC 103: How Computers Work

Spring 2016

Vocab Study Sheet

  • CPU

    CPU stands for Central Processing Unit. It is the brain of the computer and it carries out all the instructions of computer programs. It is measured in Giga Hertz (GHz). The bigger the number, the better and faster it will run with multiple programs operating at the same time. There are computers with dual, quad, hexa or octa-core processors, and more cores means a computer is of a better quality. Intel invented CPU in 1978. Today, companies are making more powerful and durable CPUs in smaller sizes.

    References:

    [1] http://www.which.co.uk/reviews/all-in-one-pcs/article/how-to-buy-the-best-pc - Which?

    [2] http://www.maximumpc.com/a-brief-history-of-cpus-31-awesome-years-of-x86/# page-1

  • Claude Shannon

    Clause Shannon was an American mathematician and engineer who in 1940 published A Symbolic Analysis of Relay and Switching Circuits in which he demonstrated that digital circuits could be represented using binary numbers, or 1's and 0's, in Boolean algebra [1]. The binary digits, or "bits", would represent the switches of a circuit [2]. The 0's would equate to open switches and no power, while the opposite for the 1's [3]. In 1948, he also published A Mathematical Theory of Communication in which he explained how information could be represented by these binaries numbers [4]. His works aided cryptography and engineering during World War II and is considered significant today because all computers utilize his theory as a basis to store and transmit information [5].

    Image from Ray Dougherty's "Claude Shannon" https://www.nyu.edu/pages/linguistics/courses/v610003/shan.html.

    References:

    [1] Encyclopedia Britannica Online, s.v. "Claude Shannon," accessed April 3, 2016, http://www.britannica.com/biography/Claude-Shannon.

    [2] Ibid.

    [3] Ray Dougherty, "Claude Shannon," New York University Linguistics Department, accessed April 3, 2016, https://www.nyu.edu/pages/linguistics/courses/v610003/shan.html.

    [4] Encyclopedia Britannica Online, s.v. "Claude Shannon," accessed April 3, 2016, http://www.britannica.com/biography/Claude-Shannon.

    [5] Rethnakaran Pulikkoonattu, "Shannon, Claude Elwood (1916-2001)," Wolfram Research, accessed April 3, 2016, http://scienceworld.wolfram.com/biography/Shannon.html.

  • GPU

    A GPU or Graphics Processing Unit is a piece of hardware that helps our computers to show images, videos, and other graphics. It is a small chip that "processes" or manages lots and lots of graphic information coded as long binary data strings, then uses said binary strings to project the images we call up. This process is called rendering. It is similar to the process of drawing something from memory. Your brain communicates the image to your hand in steps, your hand draws it, and the finished product is the doodle. Think of the GPU as the hand here- taking in information and producing an image. The popularization/invention of powerful GPUs brought upon the onslaught of beautiful and complex video games, animations, online gaming, and film.

  • George Boole

    George Boole [1] was an English mathematician who developed a type of algebra of logic, now referred to a "Boolean algebra". Boolean algebra is a way to describe continuous functions involving boolean variables, which is a basic part of digital (discrete input) circuit design. A boolean function is either true or false [2], therefore is very applicable to computing, as it is binary and discrete.

    References:

    [1] The editors of Encyclopedia Britannica, "George Boole," last modified August 31, 2015, http://www.britannica.com/biography/George-Boole.

    [2] Sara Sheehan, "CSC 103 Class Slides," last modified March 28, 2016.

  • computer

    Something that computes (turns an input into an output using a formula). A modern definition is something, usually electronic, that stores, retrieves, and processes data. Throughout history computers have changed, improving in capability and speed. The specs, including the processor, ram, and storage make up the computer as a whole.

    References:

    Notes taken in class and the Merriam Webster definition of computer

  • Moore's Law

    Based on years of observation, people found that the transistors used in a dense integrated circuit doubles approximately every 2 years.

  • RAM

    RAM stands for Random Access Memory which is commonly found in computers and used by programs. The 'memory' part refers to the hardware's ability to store data, but this memory is considered volatile because if your computer is turned off that data is lost. The 'random access' part means that you can obtain one piece of that data independently, without having to go through every other piece that comes first in the sequence, which makes it very fast. In class we acted out the function of RAM through a scripted conversation between students who carried out the instructions based on registers and memory words. The computer we were given specs for has 8GB of onboard memory, that's 1 million Bytes or 8 million bits that can store the 0s and 1s of data, which is pretty good.

    References:

    [1] "What Is Random Access Memory (RAM)? Webopedia Definition". Webopedia.com. N.p., 2016. Web. 3 Apr. 2016.

    [2] "What Is RAM (Random Access Memory)?". Computerhope.com. N.p., 2016. Web. 3 Apr. 2016.

  • byte

    A byte is a unit of measurement for computer data that is equivalent to 8 bits, i.e one byte is made up of 8 ones and zeros. Before bytes were popularized, computers signified written characters with a series of 4 or 6 bits; every computer operating system used a different number of bits as their base. However, with a series of 6 bits, it is only possible to create 64 different options and so people could only write 64 characters, which usually included upper case lettering, numbers, and some punctuation. In 1956, Werner Buchholz, one of the designers of the new IBM Stretch computer, coined the term Byte, because he wanted the new operating system to be based on 8 bits and therefore have 256 possible characters. When the IBM Stretch came on the market it was so successful that now all computers send information in Byte blocks, making it the standard measurement of computer information today. Byte is often simplified to B, so that a gigabyte would be written GB.

    One example of the current use of bytes is in the specifications of computer memory in advertisements. When an ad states that a computer can hold 8GB of memory, this means that it can remember 8 Giga Bytes (8 billion Bytes), or 64 billion bits, i.e. ones and zeros.

  • computer cooling

    Computer cooling involves removing excess heat from computer components like the CPU, GPU, and motherboard to prevent overheating, wires melting, and damage to semiconductor material, which is done through one of three methods: fans, heat sinks, and liquid.

    A fan keeps the computer cool by circulating air away from the electrical components, while the more efficient heat sink has a thermal conductor to carry heat away, dissipating it throughout the rest of the computer. In liquid cooling systems, water is circulated through pumps and loops between the heat sources and a cooling radiator, which results in a quieter and more efficient system than an air-cooled computer, but these systems have limited flexibility and may require plumbing to fix problem such as rust or leakage.

    Before the 1990s, heat sinks were only used in large computers and fans were more widely used, but heat sinks became necessary when personal computers required better cooling mechanisms with the introduction of faster processors. Lately, liquid cooling methods have become more popular, frequently used in data centers and high-end gaming PCs.

    A laptop processor with a heat sink and a cooling fan, also known as an active heat sink

    References:

    [1] "Computer System Cooling," Webopedia, accessed March 31, 2016. http://www.webopedia.com/TERM/C/computer_system_cooling.html

    [2] "Fan," Computer Hope, accessed March 31, 2016. http://www.computerhope.com/jargon/f/fan.htm

    [3] "Heat sink," Computer Hope, accessed March 31, 2016. http://www.computerhope.com/jargon/h/heatsink.htm

    [4] Robert Hartle. "How Heat Sinks Work," How Stuff Works, accessed March 31, 2016. http://computer.howstuffworks.com/heat-sink.htm

    [5] Marco Chiapetta. "Laptop makeover: 5 ways to extend its useful life," PCWorld, accessed April 3, 2016. http://www.pcworld.com/article/2137500/laptop- makeover-5-ways-to-extend-its-useful-life.html

    [6] "Water cooled," PCMag, accessed March 31, 2016. http://www.pcmag.com/encyclopedia/term/54227/water-cooled

    [7] Margaret Rouse. "Water Cooling," TechTarget, accessed March 31, 2016. http://searchdatacenter.techtarget.com/definition/water-cooling

  • computing

    Computing is to make mathematical calculations using a computer. Computing has been around since the 14th century, which was when the earliest tool of computing, the abacus, was used. To use the abacus, a person would move the beads along the rods according to what they are trying to compute. Computing has evolved from the early abacus to the modern computer, such as a Mac or a HP.

    References:

    History of Computing: http://mason.gmu.edu/~montecin/computer-hist-web.htm

    Merriam-Webster Dictionary: http://www.merriam-webster.com

  • data buffer

    A data buffer, or just buffer, is a temporary holding area where data is stored while it is in the process of being moved from one location to another. This data is typically stored in the computer's memory (RAM). For example, if you are downloading a song from the Internet, it may load the first 10% of it into a buffer and start playing the song while the rest of the song is still downloading. Without a buffer, we would have to do a lot of waiting around. The earliest form of a data buffer, called the Outscriber, was invented by Russell A. Kirsch for the SEAC computer in 1952.

    Reference (for example used)

    http://techterms.com/definition/buffer

  • hard-disk drive

    A hard-disk drive is a date storage device that stores digital information by using a single, or sometimes several, rotating disk. The digital data is stored in a random access memory (RAM) manner which means that the data can be accessed in any order. Hard-disk drives capacities are normally measured in gigabytes but, in some cases, such as the example computer "specs" that were given, it cans also have a capacity in terabytes. So, in the "specs" for the given computer, this computer has a lot of available storage on its hard-disk drive. Hard-disk drives were originally revealed by IBM in 1956 and was the size of two refrigerators and held only 3.75 megabytes.

    References:

    "What Is Hard Drive?" What Is Hard Drive? Computer Hope, n.d. Web. 04 Apr. 2016.

  • integrated circuit

    • Definition: an integrated circuit, usually abbreviated to IC, is a set of electronic circuits on one small plate made of semiconductor materials such as silicon. An IC can function as an adder, timer, counter, memory block, etc. It can be made very compact, with up to several billion transistors and other electronic components in an area the size of a human fingernail. ICs are used in computers, mobile phones, and virtually all electronic equipment. They are preferred because they have low cost and high performance.

    • Types of IC:

      1. Linear/Analog: Linear ICs have continuously variable output that depends on the input signal level. For example, an amplifier can be a linear IC, because the output should be proportional to the continuously changing input.

      2. Digital: Digital ICs only have a few defined states. For example, a logic gate or an assembly of logic gates can be a digital IC, because logic gates have only two states of output.

    • History:

      1. The first IC-like invention was made by German engineer Werner Jacobi in 1949.

      2. The idea was conceived by Geoffrey W.A. Dummer, and he public presented the idea in 1952.

      3. The first example of a working IC was demonstrated by Jack Kilby in 1958. He won the 2000 Nobel Prize in Physics for his part in this invention.

      4. The number of transistors in an IC has grown from a few in the 1960s to more than a billion now. Moore's Law indicates that the number of transistors in a dense IC doubles approximately every two years. This observation was made by Gordon E. Moore in a 1965 paper.

    • Manufacturers: some well-known IC manufacturers include IBM, Intel, Texas Instruments, and Toshiba.

    References:

    [1] integrated circuit (IC), http://whatis.techtarget.com/definition/integrated-circuit-IC

    [2] Integrated Circuit, https://en.wikipedia.org/wiki/Integrated circuit

  • motherboard

    A motherboard is the physical foundation for a computer to work. The motherboard is essentially a sheet of plastic that connects every hardware component together and allow transfer of data and information between them. One of the MacBook descriptions says "8GB of onboard memory", the "onboard memory" means motherboard's memory; "hard drive" is installed on the motherboard; "processor" is the CPU on the motherboard.

    References:

    [1] "What Is a Motherboard?" Computer Hope. N.p., n.d. Web.

    [2] Zandbergen, Paul. "What Is a Motherboard? - Definition, Function & Diagram." Study.com. N.p., n.d. Web.

  • operating system

    An operating system is the software component of a computer that supports its most basic functions. It manages all programs that the computer runs. An operating system controls activities such as the assignment of storage space, and handles input and output to and from external devices such as printers.

  • power supply

    A computer's power supply converts AC power, which is what you get out of a wall outlet, to lower-voltage DC power more appropriate for the delicate innards of a computer. Basically, what that means is that it converts alternating current to continuous current. This is done using a transformer, which lowers the voltage of the current, a set of diodes, which converts the power from AC to pulsating, and finally then to DC voltage using an electrolytic capacitor.

  • semiconductor

    Semiconductors (the most common of which is silicon) are electrically conductive substances that, depending on conditions such as temperature, can also act as insulators. Semiconductors are particularly useful in computer technology, as their dual-properties can be harnessed for the blocking or passing of electric current. Transistors, which make up integrated circuits and convey information in binary, use semiconductor materials to pass electric current, and subsequently information. Large vacuum tubes were used for this purpose prior to the introduction of semiconductors in the mid-20th century. Semiconductor materials have radically changed the computer science industry, as increasingly smaller amounts of material are required to build transistors, which are the building blocks of modern computers.

    References:

    [1] WhatIs.com: Definition semiconductor, http://whatis.techtarget.com/definition/semiconductor

    [2] Merriam-Webster: Full definition of semiconductor, http://www.merriam- webster.com/dictionary/semiconductor

    [3] University of Maryland: Materials Science and Engineering: Semiconductors, http://www.mse.umd.edu/whatismse/semiconductors

    [4] Maxim Integrated: Glossary Term semiconductor, https://www.maximintegrated.com/en/glossary/definitions.mvp/term/Semiconductor/gpk/1003

    [5] Big Think: A Brief History of Moore's Law and The Next Generation of Computer Chips and Semiconductors, http://bigthink.com/dr-kakus-universe/a-brief-history-of-moores- law-and-the-next-generation-of-computer-chips-and-semiconductors

    [6] Course lectures and PowerPoints

  • transistor

    From: https://simple.wikipedia.org/wiki/Transistor#/media/File:Transistor_basic_flow.svg

    Transistors are the building blocks of electronics; they amplify and transmit signals. They are made of semiconductors (materials that can either help or hinder the flow of electricity) and have at least three terminals that can connect it to circuits. When electricity is sent through one of its terminals, it can change the current and switch signals on or off; this sends signals in binary (a number system used by computers where numbers are represented by combinations of zeros and ones; "zero" and "one" can also be read as "off" and "on") to the computer so that it can process instructions.

    The transistor was invented at the Bell Laboratories in 1947 by John Bardeen, Walter Brattain, and William Shockley as an alternative to the vacuum tube (a different transmitter of signals that was less reliable). However, the name "transistor," short for "transfer resistance" or "transresistance," was coined in 1948 by science-fiction writer John Pierce.

    References:

    [1] "Transistor" entries on Wikipedia, in both English and Simple English https://en.wikipedia.org/wiki/Transistor https://simple.wikipedia.org/wiki/Transistor

    [2] "Transistorized!: History" on PBS http://www.pbs.org/transistor/album1/

    [3] "Transistorized!: History: Namint the Transistor" on PBS http://www.pbs.org/transistor/album1/pierce/naming.html

    [4] Computer Hope dictionary entries on "transistor," "CPU," and "binary" http://www.computerhope.com/jargon/t/transist.htm http://www.computerhope.com/jargon/b/binary.htm http://www.computerhope.com/jargon/c/cpu.htm

  • truth table

    A truth table is a table used to solve and show the functions in logic gates. This can be done using 1s and 0s, or T (true) and F's (false). The table works by having the inputs on one side, and the output (or outputs) on the other. Each table has a function that you solve using the input values. The solution to the function becomes the output and determines whether the function is true or false.