Hello. Today we are revisiting an old “word to the wise”, File extensions:
For example: .txt, .jpg, .pdf
Definition:
A file extension is the last part of a file name, the bit after the dot (e.g. Myfile.pdf). Most are three characters long, but they can be longer or shorter.
They are used to define the file type of each file. For example, “.jpg” would be a picture, or “.txt” would be something you wrote in notepad.
Windows uses the file extension to select which program will open the file. E.G double clicking on “example.jpg” will open the file in a picture viewer, like Picasa or Windows Live Photo Gallery.
Common file extensions:

  • .doc – Microsoft Word Document
  • .txt –  Text file
  • .ppt – Microsoft Powerpoint presentation
  • .mp3 – MP3 Audio file
  • .wma – Windows Media Audio file
  • .avi – Audio Video Interleve file
  • .wmv – Windows Media Video file
  • .jpg – JPEG Image
  • .bmp – Bitmap Image file
  • .zip – Zipped (compressed) file
  • .pdf – PDF file
  • .exe – executable files (often a program)

I hope you found this useful!
Georgia