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Interacting with a computer (in the MathCS lab)

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• Before we can program a computer...
  • Before we can learn to instruct a computer, we must first learn to:

    interact with a computer

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  • Devices used to interact with a computer:

    Mouse Touch pad           Keyboard

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  • For casual computer users, the most important interaction device is:

    mouse (and a little keyboarding for chatting)...

  • For computer programmers, the most important interaction device is:

    keyboard !!!

    because they must write programs in an English-like programming language

    (I dare you to write a book using a mouse by clicking on a virtual keyboard !)

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• Gaining access to the MathCS computer system: log in
  • The MathCS computer lab is located on the 3rd floor of the MSC building

    The lab hours and rules can be found at this webpage: click here

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  • You can log in (= gain access) to any computer in the MathCS lab using:

    your Emory ID your Emory password

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• Computer Operating Systems
  • Every computer is controlled (= "managed") by a very complex computer program called an Operating System (OS)

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  • The Operating System (OS) controls:

    The mouse The keyborad The monitor The disks ... Every component of the computer !!!

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  • The Operating System (OS) can also:

    Detect mouse clicks Detect key strokes Load a computer program from hard disk into RAM memory and execute it

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• Today's most popular Operating Systems
  • Microsoft Windows

    First developed in 1980 for the IBM-PC by Microsoft Mostly used in PCs           A history of Windows: http://windows.microsoft.com/en-US/windows/history

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  • UNIX

    First developed in the early 1970's for min-computers by AT&T Used in PCs, and servers           A history of UNIX: http://www.unix.org/what_is_unix/history_timeline.html

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  • MAC OS

    First developed in 1984 for the Macintosh PC by Apple Used in Apple's computers           A history of MAC OS: http://en.wikipedia.org/wiki/History_of_Mac_OS

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• Executing a program through mouse clicks
  • For PC users, the most common way to run a computer program is through mouse clicks

    Example:

    When you want to run the FireFox web browser, you double click on the FireFox icon:

  • This is what is going on inside a computer when you (double) click on an icon that is associated with a compter program:

    You double click on an icon The Operating System detects the mouse clicks on the icon The Operating System locates the program that is associated with the icon into RAM and execute it

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  • In Microsoft Windows, you can find out which program is associated with an icon by right-click the icon and select properties

    Example:

    The Target field in the "properties" window shows the path of the program that will be executed when you double click the icon.

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• Executing a program through a keyboard
  • Every computer system provides an application that allows the user to type in the path of the program that he/she wants to execute

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  • Application name:

    Microsoft Windows: cmd (command line tool) UNIX: sh (the original Shell), csh (C Shell), ksh (Korn Shell), bash (Born Again Shell), MAC OS X: Terminal (it is in fact a UNIX shell program)

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  • Example: running FireFox using cmd in MicroSoft Windows:

    On your PC: click START and run cmd In the cmd window, type the complete path of the FireFox application: Note: make sure you quote the entire command !!!