(i) Amazon
(ii) Trash
(iii) Files
(iv) System Settings

All the Operating system based on the concept of GUI (Graphical User Interface).

Choose an option logout through the session indicator on the far right side of the top paner.

The server distributions in Linux OS
(i) Ubuntu
(ii) CentOS
(iii) Red Hat
(iv) SUSE
(v) Fedora

(i) The Open source software is free to use, distribute, and modify.
(ii) It has lower cost in most cases in only the fraction of the cost of their proprietary counter parts.
(iii) It is most secured as the code is accessable to everyone.

"Save" option save a document in first time. "Save As" option save an already saved the document with a new name and also create a copy of already saved document with a new name obviously.

File extension is used to know that in which the file is associated with.

Five fox is a browser. Thunderbird is email client which can be used view emails received.

(i) Due to low capacity of main memory (RAM) the system many hang while working with multiple files.
(ii) To reduce it increase the size of main memory and other reasons for hanging is over heating, driver corruption or errors, software errors and computer virus.

Finding Files and Folders : You can use the search box on the Start menu to quickly search a particular folder or file in the computer or in a specific drive.
To find a file or folder:
(i) Click the Start button, the search box appears at the bottom of the start menu.
(ii) Type the name of the file or the folder you want to search. Even if you give the part of the file or folder name, it will display the list of files or folders starting with the specified name.
(iii) The files or the folders with the specified names will appear, if you click that file, it will directly open that file or the folder.
(iv) There is another option called "See more results" which appears above the search box.
(v) If you click it, it will lead you to a Search Results dialog box where you can click and open that file or the folder.
Searching Files or folders using Computer icon :
(i) Click Computer lcon from desktop or from Start menu.
(ii) The Computer disk drive screen will appear and at the top right corner of that screen, there is a search box option.
(iii) Type the name of the file or the folder you want to search. Even if you give the part of the file or folder name, it will display the list of files or folders starting with the specified name.
(iv) Just click and open that file or the folder.

Application Icons:
(i) These icons are representing Software package's logo. Double-click over this icon, the related application gets invoked.
(ii) Shortcut Icons: These icons point to a particular application or file or folder. By double clicking over them the related application or file or folder will open. This represents the shortcut form to open a particular application.
(iii) Document Icons: Active document window which is a window within an application window is called as the document icon.