computer skill note ( COSK )

Operating system functions

Operating System is a software program that acts as an interface between the user and the computer. It is a software package which allows the computer to function.

To act as interface between hardware and users, an operating system must be able perform the following functions:

1. Enabling startup application programs. Thus, the operating system must have:

- A text editor , A translator , An editor of links

2. The allocation of resources needed to execute programs is done by identifying: the programs that are running, the need for memory, peripheral devices and data protection requirements.

3. Facilities for data compression, sorting, mixing, cataloging and maintenance of libraries, through utility programs available.

4. Plan implementation works according to certain criteria, for efficient use of central processing unit.

5. Assisting implementation of programs through computer-user communication system, at both hardware and software level.

And also others Functions:

Program creation  , Program execution  , Access to Input/output devices , Controlled access to files , System access , Error detection and response , Interpreting the commands , Managing peripherals , Memory management , Processor management  , Information management , Process communication  , Networking

Basics components of Windows

The main components of Windows when you start your computer are the Desktop, My Computer, Recycle Bin, Start Button, Taskbar, and shortcuts to applications.

After opening an application, you will also have a window with an active application which will appear in your desktop and taskbar.

Desktop:- The image of a desktop was invented to make computers easier to use. The more you compare this desktop with the situation behind a real desk, the faster you will understand it.

Each desktop may look slightly different and show different objects (icons and buttons). Look on your screen and see if you can find the three icons on the right. Each object on screen represents a Function. You get access to these functions by touching them with the mouse and cursor.

Recycle Bin:- Here we introduce the most important objects of the desktop. The 'Recycle Bin' is a special folder. Like a real waste basket, you can use it to dispose of things you no longer need. You can put

Documents in it and take them out again, until you empty it.

My Computer: - This icon symbolizes your computer. You use it to get access to documents or programs on a Floppy-disk or a CD.'My Computer' also gives access to the 'hard disk': the place within

the computer where the programs and documents are kept.

S t a r t - b u t t o n :- The 'Start'-button gives you access to different functions, like starting programs and shutting down the computer. When a document is lost, you can use the Start-button to help you find it.

Taskbar: - The Start-button is part of the 'Taskbar'. For each program you start, a button is added to the Taskbar. This means you can open and use more programs at the same time. When you want to

Switch between programs you only click on its button in the Taskbar.

Cursor: -  The white arrow is the 'cursor'. You use it to tell the computer what to do. You can move it on the screen by moving the mouse with your hand. Try to move it to all four sides of your screen.

F o l d e r :-  The yellow icon is a 'Folder'. Like a real folder or cabinet, you can use it to store things on the computer. You create your own folder(s) for your documents

Computer icon

A computer icon is a pictogram displayed on a computer screen and used to navigate a computer system or mobile device. The icon itself is a small picture or symbol serving as a quick, intuitive representation of a software tool, function or a data file accessible on the system. It functions as an electronic hyperlink or file shortcut to access the program or data. Computer icons, in conjunction with computer windows, menus and a pointing device, form the graphical user interface (GUI) of the computer system, and enable the user to easily and intuitively navigate the system.

Using Desktops

A desktop allows you to organize applications on up to four virtual desktops. Read email on one, browse the web on the second, and do work in your productivity software on the third, without the clutter of the windows you're not using. After you configure hotkeys for switching desktops, you can create and switch desktops either by clicking on the tray icon to open a desktop preview and switching window, or by using the hotkeys.

Unlike other virtual desktop utilities that implement their desktops by showing the windows that are active on a desktop and hiding the rest, Desktops uses a Windows desktop object for each desktop. Application windows are bound to a desktop object when they are created, so Windows maintains the connection between windows and desktops and knows which ones to show when you switch a desktop.

Activating windows

Microsoft Product Activation is a form of digital rights management used by Microsoft Corporation in several of its computer software programs, most notably its Windows operating system and its Office productivity suite. The procedure enforces compliance with the program's end-user license agreement by transmitting information about both the product key used to install the program and the user's computer hardware to Microsoft, inhibiting or completely preventing the use of the program until the validity of its license is confirmed.

When installing a retail copy of Windows or Office, the user is asked to input a unique product key supplied on a certificate of authenticity included with the program, which is later verified during activation. Immediate activation is not required following installation, but the program must be activated within a specific period of time in order to continue to function properly. Throughout this grace period, the user will be periodically reminded to activate the program, with warnings becoming more frequent over time.

Activation is performed with a utility supplied with Windows and Office called the Activation Wizard. It can be performed either over the Internet or by telephone. When activating over the Internet, the Activation Wizard automatically transmits and receives verification data to and from Microsoft servers, completing the process without any interaction by the user. Activation by telephone requires that a user and a Microsoft agent verbally exchange activation information. In this case, an installation ID is generated, which is then be read to the agent. The agent verifies the information and replies with a confirmation ID, which is then typed into the Activation Wizard