File Extensions, etc
Video on WinXP backup http://urlsnip.com/843271
Freeware & free software: http://100-downloads.com/
URL How to back up and recover Outlook Express data http://urlsnip.com/206208
What are file extensions
They are the last characters (suffixes) after the dot in the name of a file.
Designate what type of files they are e.g. .doc uses MS Word and Wordpad
Prior to Windows i.e. DOS (Disk Operating System), every file was named with a maximum of eight characters with a three letter extension
Now character limit is about 253
They are obvious on the Internet, computer literature, etc
Your PC must know how to handle a file if it does not have an extension
Why make them visible
They are hidden by default
Makes more sense to show them i.e. computing faster and easier.
Helps protect from viri and Trojan horses e.g. trick file looks like file JPG but is an .EXE
How can I make them un-hidden
My Computer; Tools; Folder Options; View; under Files And Folders listing, uncheck Hide extensions for known file types; click Like Current Folder; OK
What happens if extension is unregistered (no association in the Windows Registry)
Open With dialog box occurs > allows you to decide what program to use
Examples of downloadable programs to open file
Examples: Adobe Reader for PDF; Power Point Reader for Power Point
Some do not have extensions e.g. HOSTS (open with Notepad)
What are some common types
bmp Bitmap files (graphics)
doc Document File, e.g, MS Word
gif Graphics Interchange Format (graphics)
jpg Joint Photographic Experts Group (graphics)
pdf Portable Document File e.g. Adobe Reader
htm Hypertext Markup (special coded text files)
html Hypertext Markup Language (ditto)
tar Same as zip. Just another compression style
wav Sound files
txt Text File, such as Notepad produces
zip Compressed file requiring special software to decompress the file
URLs for problem in identification of an extension: