When you first start the computer, and wait for it to finish doing everything, you finally get to the Desktop. The desktop is made up of five sections.
Fig 1.0 The Desktop Icons - The main part of the desktop
Fig 1.1 The START Button
Fig 1.2 The Taskbar - The Icons on the left side of the START button are for Permanent (Regular) Tasks
Fig 1.3 The Taskbar - The Taskbar - The Icons in the middle are for Temporary (Currently Opened) Tasks
Fig 1.4 The Notification Area
With the desktop now identified, and with the knowledge that the Desktop Icons (Fig 1.0 above) make up the main part of the desktop, the next questions is: What is an icon?
An icon is simply an image that is designed to represent a file, or folder, so that you have some idea of what that file does or what is inside the folder. For example: An icon with a Document image might be representing the Letter (data) file itself or the Word Processor (program) file whereas an icon with a Paint Brush image might be representing a painting (program) file or just the photograph (data) itself. An icon with a Folder image though normally represents a folder and more importantly what is inside that folder.
When you double click (press the left mouse button twice, quite fast on the same spot) on an icon Windows 10 first determines what file is associated with that icon. If it is a Paint (program) file for example (i.e. Paint.exe) Windows 10 will launch that painting program only, but if it is a Photograph (data) file (i.e. John.jpg) Windows 10 will launch the painting program before instructing it to automatically open/display the photograph file for you.
Fig 1.5 A Double Click on this icon would start Notepad
Fig 1.6 A Double Click on this icon would start Internet Explorer 11
The rest of the desktop is made up of the other four items (Figures 1.1 to 1.4 above), which are joined together to make one standard bar at the bottom of the screen, like so:
Fig 1.7 The START Menu button, the Taskbar and the Notification Area combined
The START Menu button is the starting point from where you can Launch Software, Change Settings, Find Folders and Get Help among other things. I will show you more of this later.
The taskbar, formerly known as the Quick Launch Toolbar, allows you to quickly launch software with only one click of the left mouse button. For example: If you want to launch Windows Media Player from the desktop you must double click on the Windows Media Player desktop icon, but with the taskbar (quick launch toolbar) you only need to click on the Windows Media Player task (quick launch) icon.
Fig 1.8 A Taskbar Icon (quick launch toolbar icon) only needs one Click
Fig 1.9 A Desktop Icon needs a two Clicks (a Double Click)
Note - A program or piece of software might still refer to the Quick Launch Toolbar when installing something for example, which means that program or piece of software was made for Windows XP (or an earlier operating system) but not 100% for Windows Vista, Windows 7 or Windows 10. Therefore, try to avoid such software installations by seeing if a later version of that software is available (i.e. a Windows 10 version).
Whenever a new task (program) is opened, whose icon is not already 'pinned to the taskbar' (made permanent on the taskbar, via a setting), it leaves an icon on the taskbar to let you know it is still running (still working/open). In this example (below) the Printer icon is on the taskbar, to let me know that my Canon Printer is still running. When a task is closed its taskbar icon disappears, to let you know the task has closed and is no longer running, if its icon hasn't been 'pinned to the taskbar'. The taskbar is also used when Minimizing/Maximizing a window - For more information see the Windows section.
Fig 1.10 The printer icon on the taskbar means the printer is still ready for work
The Notification Area is similar to the Taskbar (quick launch toolbar) except that it is aimed at managing programs that do not normally need launching manually, by you, simply because these types of program have usually launched themselves already during the start up of Windows 10 - Usually programs associated with Anti-Virus, Broadband, the Printer and so on. If they need some sort of attention (i.e. updating or have closed) you are warned of this by way of a Notification (i.e. pop-up message).
The notification area used to be called the System Tray. So if you see a program using that terminology, you know it was made for Windows XP for example but not 100% for Windows Vista, Windows 7 or Windows 10.