create using an application program is stored in a special format. If you use a different application program to read that file, you may encounter problems.

Each file must have a unique filename so you can retrieve it when you need to. The filename consists of two parts: the name and the extension.

You can choose a name up to eight characters long. Create a name that identifies the information the file contains. The name can contain any characters or numbers except for blank spaces and the following symbols:

The extension is optional and can be up to three characters long. You can use the extension to further identify a file or to describe what type of file it is, such as a text file or program file. When you use an extension, separate it from the filename with a period. For example, an MS-DOS filename might look like this:

DATA.TXT

Some application programs add extensions to the files you create. These application programs use the extension to determine whether it is a compatible data file. Avoid using extensions used by your application programs. Also, do not use uppercase and lowercase letters to distinguish between files. MS-DOS does not recognize the difference and displays all filenames in uppercase.

Using Directories

MS-DOS organizes files by storing them in directories. This makes it easy for you to find and manage your files. Directories contain specific information about each file such as the filename, the file size, and the date and time you last updated the file.

To group files more efficiently, you can create subdirectories. This kind of organization is called a tree-structured directory. At the top of the tree- structured directory is the main directory, which is called the root directory

The root directory can contain many subdirectories, and each subdirectory can contain other subdirectories. A directory that contains subdirectories is called a parent directory.

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Using MS-DOS with Your Equity Ie