If you’re a Windows power user you probably already know how to do this, but for everybody else, it can be useful to see file extensions so that you know for sure what type of file you are dealing with.
This can also help in situations where you download what you think is a PDF file, and the real extension is .pdf.exe, which means you downloaded an executable program file, which is most likely a virus. So by showing file extensions you can verify that you are really dealing with a .pdf file. (Note that PDF files often have their own security problems)
About File Extensions
File extensions are the short three of four letter codes separated from the name of a file by a period. These indicate the type of file you are dealing with, and tell your operating system what program to use for opening these files. For example, audio files come in many formats including: .wav, .wma, .aac, and .mp3.
By default, Windows hides these extensions to prevent users from tampering with the file names and rendering them useless. This is handy for people who aren’t very familiar with computers, but sometimes you need to see what they are.
Making Windows Show File Extensions
There are two main methods you can use for toggling the “Show File Extensions” feature in Windows. The first will require you to go through the control panel, while the second only requires that you open an Explorer window.
Using Control Panel
Begin by opening the control panel, and then click on “Appearance and Personalization.”
Next, you will need to click on the “Folder Options” section.
Under the “View” tab, in the “Advanced settings” box, deselect the “Hide extensions for known file types” option.
Lastly, click “Apply” then “OK” to complete the process. Now you will see the file extensions of every file shown at the end of their names as shown in the image below.
Using an Explorer Window
First, you will need to open up ay explorer window. For this example, we will use the “Documents” folder. Simply press the “Alt” button to being up the classic menu bar on the top of the window, then select the “Tools” dropdown menu, and click on “Folder Options.”
Now just untick the “Hide extensions for known file types” option from the “View” tab, as shown in the last method.
If you ever need to hide the extensions of your files, simply go through the same procedure and ensure that the “Hide extensions for known file types” option has a checkmark.