All data on a computer is stored in collections called files and folders. A file is the most basic collection of data on a computer. A file can store the instructions for a single program, or the data for a single letter. Folders are collections of files. So a file is like a piece of paper and you put it in a folder.

Files Files are the most basic data collections, they store the data for a single thing.

Folders Also called directories, folders are collections of files.

It is very necessary to sort files properly into folders so that you can find them again. Many people have had to redo entire projects because they lost their file by putting it into the wrong folder. Most files are named with two parts. The first part of the filename is a description of the file. After this comes a ‘.’ followed by the second part. The second part of a filename is called the extension. Extensions are often three letters long and they tell you what kind of file it is. For example ‘exe’ files (files with an extension of ‘exe’) are programs. ‘Doc’ files are Microsoft Word documents.
Besides saving (taking a file you have open in a program and writing it from memory onto a disk) there are many other file operations. These can all be done using the same program. This program is a utility called a file manager. There is a file manager that comes with Windows called Windows Explorer, or sometimes just Explorer. To open Explorer go to ‘Start>Programs->Windows Explorer’ or ‘Start->All Programs->Windows Explorer’.

NOTE: This is a standard computer notation for menus. When you see something that goes ‘M1->M2->...’ or sometimes ‘M1 > M2 > ...’ it means that you are to open the menu item M1 and then open the sub-menu M2 etc. and the final item is the menu item to click on. Obviously, ‘Start’ is the start-menu.