Displaying File Extensions

Description of the Topic

Each file on your computer is designated by a Filename followed by a period (.) and a two-, three- or four-letter Extension. The Filename can be anything chosen by the person who created the file (you or someone else) and can be up to 256 characters in length, though most are much shorter than that. Its purpose is to help to remind you of the contents or purpose of the file. The Extension tells Windows what kind of file it is and which program to use to open it. There are many different Extensions, each with its own meaning. Some examples:


Executable Files
Word Documents
Excel Spreadsheets
Text Files
Joint Photographers Group photo
Bit-mapped Graphic photo


Graphic Interface Format image
Tagged Image File format
Compressed Video and Audio
Compacted File
HyperText Markup Language (Web) File
Portable Document Format

If you are unable to tell what Extension a file has, it will be difficult or impossible to manage your files properly.

Microsoft decided for some reason many years ago, when the first Windows operating system was introduced, that we users would be better off not knowing this stuff. Well, they were wrong. Knowing what Extension a file has gives you the ability to determine how it should be handled by your computer and, when there are two files with the same name, to distinguish between them. One of the first things you should do when you get a new computer is to enable the viewing of File Extensions.

If you come across an Extension and you don't know what kind of file it represents, check with Extension Search to get the answer. For more information about File Extensions, visit Stack.com, File Extension Info or What are File Extensions and What Do They Do?

How to Display File Extensions (video demonstration)
How to Display File Extensions (step-by-step procedure)
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