Data In, Data Out
by Bill O’Kane, Alternative Business Systems
As opposed to the Operating System (O/S) which is built to do many tasks well, application software is usually intended to do one particular task. The range of software applications available is astronomical and any task that is capable of being accomplished on the computer has software to assist the user.
Computer software allows graphic artists and moviemakers to create worlds that exist only in the artist’s minds. Audio editing software allows users to record, edit, and create music that would have required thousands of dollars in recording equipment only a few years ago. Video editing software allows users to capture video and edit it adding sound or captions. Web applications allow users to communicate, study, do research, or just entertain themselves. And the list is endless.
MS Windows O/S has evolved from version 3.X to 9X to ME to 2000 to XP. It contains many basic applications already installed with the operating system, such as text editors, graphics editor, sound recording, video recording and playback, and web tools. As stated the tools included are of a very basic nature and for advanced use more powerful applications are required.
Luckily, installing MS Windows applications is an easy task. Most modern applications are a single executable file (application themselves), a compressed archive, or come on disk with a set-up program. The installation usually only requires the user double click the set-up program and the application will take them step-by-step through the set-up process. Most modern installations will create a shortcut icon to the application on your desktop or in your “Start” menu.
Note to MS Windows users: It is important to use the uninstall utility included with the program or the Windows uninstaller when removing programs. Not doing so can leave files lying around that can cause problems in the future. We will go into this in more depth when we explore the Windows desktop.
There is one more specialised piece of software I should mention before we try booting the system. These applications are called hardware drivers. Let us take as an example a video card installed on your machine. The driver software is created by the card manufacturer and is something like a translator. When Windows wants to communicate with the card or vice versa the software driver acts as a go between, assuring that the card and the O/S send and receive intelligible messages. These drivers install very much like any software but you do not have to start them like other applications, the O/S will start them automatically during the boot when it detects the device. One word of warning: these drivers are specific to the card model and the O/S, and in most cases will not work with different cards from the same manufacturer. The drivers are usually included when you buy the card or may be included in the OS itself.
Let’s take a quick tour of a boot and see what happens. The process and order differs a bit between systems but all are basically the same. When you switch on the power, small applications built into the computer’s main board run a Power On Self Test (POST). Most failures in this process will cause a stop error and present you with an error message.
- (Depending on the system the screen now contains text and can scroll by quite quickly)
- The power supply fan and CPU fan spin up.
- The hard drive begins to spin up to speed.
- The CPU, video and system bus are tested and initialised.
- The CD and floppy drive are initialised.
- The system checks for a keyboard.
- The POST checks the memory by writing and reading data and comparing the two.
- A quick series of tests are run on other system devices.
- The system checks for a special sector on the floppy drive called a boot sector, if it finds none it performs the same check on any disks in the CD drive.
- The system now checks for the same sector on the hard drive. If the sector is found the boot process is now handed over to the hard drive and the installed operating system.
- Once the operating system has control of the boot it begins a series of checks to see if the files it needs are available.
- (By this point a graphical screen appears, depending on the operating system version)
- It searches for hardware and installs any required drivers.
- It adjusts setting to any configuration files
- You are presented with a login screen (depending on your setting) Once you log in you will be presented with your desktop. You do remember your user name and password don’t you?
See, all you really have to do is supply some power and sit back while your computer gets ready for your commands. In the next article we get to the real fun stuff. We will take a look at the desktop, the file system, and the Windows Control Panel.
Now find that power button! Push it. You can.
Contact Bill O’Kane at: Alternative Business Systems
36 Bradd Street
Miramichi, New Brunswick