OPERATING SYSTEM

INTRODUCTION :- An operating system has two parts : Kernel and Shell. The kernel is responsible for interacting with hardware and shell is responsible for interacting with user. The shell acts as the command interpreter which takes the commands from the user, interprets them and then take action accordingly.

GUI (Graphical User Interface) based operating systems have shells that offer graphical elements for interaction.

WINDOW 7 OPERATING SYSTEM

Microsoft window 7 is a GUI operating system that adheres to the features of a good GUI. Multiple applications can be simultaneously run in different window. Apart from this multi-tasking (i.e. simultaneously running multiple applications), a number of concepts and terms are available in window and that is what we are going to briefly discuss here in this section.

The windows operating system uses both mouse and keyword as input devices. Interaction with windows or a windows application is most efficient when options are chosen with mouse and characters are entered via the keyboard.

While working with mouse 

•   Point and click the left button to select an item. A selected item is highlighted in some way. Selection  of an item does not result in the initiation of a process 
•   Point and double click left mouse button to choose an item. When you choose an item, some kind of action occurs.  
•    Right click (press and release the right mouse button once) to display the shortcut menu. A shortcut menu is a menu that shows the most frequency used commands for that selected file or folder for which the mouse has been right clicked.
•    Point and drag (press mouse button and while pressing move to another location and then release the mouse button) to move or resize a window on the display screen.

While working with the keyword 

     Ø  Activate the current menu box by tapping the ALT key.

     Ø  Enter the underlined letter of the menu option in the active menu to choose that option.

     Ø  Arrow keys may be used to highlight menu options.

     Ø  Shortcut keys ( a key or a key combination e.g. Alt + f4 for closing an application) can be used to issue commands within a particular application without activating a menu.

WINDOW FEATURES

Window is one of the moist popular GUI operating system of today’s world. It has got some very useful features that add to its user-friendliness. Let us see about them one by one.

     (a)    THE DESKTOP

fig (a). The Desktop

     The worlds desktop has been derived from real life desk top where a manager puts all the things required by her. For instance on a desktop there may be a pen-stand, note pad, calculator, file folder etc lying which are required by the manager. The desktop of a window also serves the same purpose

In window operating system, the screen upon which icons, windows etc are displayed is known as desktop. The window operating system desktop may contain a background, one or more active or inactive windows, a taskbar and icons as shown in fig. A background can be anything from a single colour screen to an elaborate artistic image. All windows and icons are superimposed on the background whatever it may be.

THE WINDOW

A window is a typical rectangular area pertaining to an application or a document of a dialog. Fig shows application and document window and next fig shows a dialog window.

VARIOUS TYPES OF WINDOW APPLICATIONS AND DOCUMENT WINDOWS

Let us discuss each of these window types in details.

(i)                  THE APPLICATION WINDOW :- An application window contains an open application i.e. a running application such as word or paint. Several applications can be open or running simultaneously, but there is only one active window at any given time

An application window has many elements : the title bar, the menu bar, the workspace, the scroll bar and the corners and borders. Each of these is being described in the following lines.

Fig. The Application Window

THE TITLE BAR

It is the topmost horizontal bar of each application window and it contains the title of the open window. Apart from the title, it has several other elements also viz. application icon, active file name minimize button, maximize/restore button and exit button.

It is the icon representing the open application. When you click at application icon, a pull down control menu appears which is also called system menu. Control menu options vary depending upon the type of application being displayed in the window.

THE MENU BAR

The menu bar for an application window is a horizontal bar just below the title bar. The menu bar lists the menus available for that application. Choosing an option from the menu bar results in pull down menu.

THE WORKSPACE

This is the area in a window below the title bar and menu bar. Everything that relates to the current application is displayed in the workspace.

THE SCROLL BAR

Depending upon the size of a window, the entire application may not be visible. When this happen, the window is outfitted with vertical and/or horizontal scroll bars. Each scroll bar contains a scroll box and two scroll arrows. Keyboard movement keys and mouse can be used to move scroll box up/down or left/right on a scroll bar to display other parts of the application.

CORNERS AND BORDERS

To resize a window, use the mouse and point to a window’s border or corner. The mouse currently changes to a double arrow when positioned over a border or corner. Drag the border or corner in the direction indicated by the double arrow to the desired shape.

2. THE DOCUMENT WINDOW

The document window are the windows within an application window. These afre displayed in the parent application window’s workspace. There can be multiple document windows open in the application window.

THE ICONS

As you know, icons are the preety pictures representing windows elements like files, folder, shortcuts etc. icons play a very important role in graphical user interfaces. Commonly used icons are : application icons, shortcut icons, document icons and disk drive icons

Let us see what these are :

APPLICATION ICONS

These are the graphic renderings of the software package’s logo. If you double click over this icon, the related application gets invoked.

SHORTCUT ICONS

These are little graphics pointing to a particular application, document or folder etc. By double clicking over the them the concerned application/document/floder etc becomes active.

DOCUMENT ICONS

The active document window, ehich is a window within an application window, can be minimized to a document icon. Point and double click on the document icon to restore the document window.

DISK DRIVE ICON

The disk drive icons graphically represent five disk drive options : floppy disk, hard disk, network, CD-ROM/DVD drive, pen drives

Typically PCs have only one or two floppy drives assigned to A and B and hard disk drives are named as C onwards.