Introduction to Computers

Charles Babbage “Father of the Computer” Created the first concept of a programmable computer in 1822 His machines were designed to contain tens of thousands of precision-made gears He never actually built any of his designs

The Difference Engine In 1991, Babbage’s difference engine was built If it had been completed, the difference engine would have had 25,000 parts and weighed 15 tons

Herman Hollerith Designed a punch card system to calculate the 1880 census Reduced a ten year job to three months Saved the government $5 million Founded the company that became IBM

George Stibitz “Father of the Modern Digital Computer” Discovered the use of relays for automated computing in 1937

Alan Turing “Father of Computer Science” Invented the Turing machine in 1936 Turing machine can be considered a model of a general purpose computer

Grace Hopper Programmed the Mark I Computer during WWII Led the team that created the first computer language compiler Popularized the term “computer bug” when a moth was found inside the Mark II computer

History Continued Vacuum Tubes Transistors Integrated Circuit An electron tube containing a near-vacuum that allows the free passage of electric current Transistors A semiconductor device used to switch electronic signals Integrated Circuit An electronic circuit formed on a small piece of semiconducting material

Modern Computers

Hardware and Software Hardware Software Electric, electronic, and mechanical components The machines, wiring, and other physical components of a computer Software The programs and other operating information used by a computer Software tells the computer what tasks to perform and how to perform them

The Components of a Computer Input – Allows users to enter data or instructions into a computer Output – Hardware that conveys information System Unit – Case that contains the electronic components Storage Device – Device that holds data, information, and instructions Communication Device – Enables a computer to send and receive data, instructions, and information to and from one or more computers or mobile devices

Input An input device is a piece of computer hardware equipment used to provide data and control signals to the processing system of the computer Examples of input devices include keyboards, mouses, scanners, digital cameras, and joysticks

Output An output device is any device that receives data from a computer, usually for display, projection, or physical reproduction Examples of output devices are monitors and printers

Storage Device In this class, we will define a storage device as anything that connects to a computer for the purpose of storing data Examples of storage devices are USB drives, CD/DVD drives, hard disk drives, and card reader/writers

System Unit A system unit is what holds the components of a computer This is also commonly known as a tower, or simply referred to as a desktop computer

The Components of a Computer Image borrowed from http://biobio.loc.edu/chu/web/Courses/COSI118/lecture/hardware.htm

Ports on a Computer A port is a physical docking point to which an external device can be connected External devices are connected to a computer using cables and ports Ports are slots on the motherboard where a cable can be plugged in Examples of external devices attached via ports are mouses, keyboards, monitors, microphones, speakers, etc.

Inside a Computer Motherboard – the computer’s main circuit board, a thin plate that holds the CPU, memory, connectors for the hard drive and expansion cards, and connections to the computer’s ports CPU/processor – the central processing unit, sometimes called the brain of the computer RAM (random access memory) – short term memory, which temporarily stores data until needed Hard drive – long term storage, where data is saved even when the computer is turned off Power supply unit – converts the power from the wall outlet to the type of power needed by the computer

Types of Computers Personal Computers Mobile Computers and Mobile Devices Game Consoles Servers Mainframes Supercomputers Embedded Computers

Personal Computer A computer designed for use by one person at a time

Mobile Computers and Mobile Devices A portable computing device such as a smartphone, tablet, or laptop

Game Consoles A specialized desktop computer used to play video games

Servers A computer or computer program that manages access to a centralized resource or service in a network

Mainframe A large, high-speed computer, especially one supporting numerous workstations or peripherals

Supercomputer A computer with a high-level computational capacity compared to a general-purpose computer

Embedded Computer A special purpose computer that functions as a component of a larger product Calculators ATMs Thermostats Cameras Printers

Operating Systems The operating system is software that supports a computer’s basic functions, such as scheduling tasks, executing applications, and controlling input/output The operating system manages the application that are installed on the computer Examples of operating systems are Windows, Mac OS X, and Linux

Applications An application is a computer program designed to perform a group of coordinated functions, tasks or activities for the benefit of the user Examples of applications include Google Chrome, Microsoft Word, and Adobe Photoshop (these are just a few – there are many more)

Links for Further Study http://www.gcflearnfree.org/computerbasics/