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TECH TIP: 3 letter extensions - are they important?

3 letter extensions at the end of a file name are very important to PCs. They are not important to Macs. On PCs, they tell what program or application will open the file.

Examples: My Bio.doc (this is a Word Document). Letter to Grandma.wpd (this is a Word Perfect document. Emma.jpg (this is a photo or picture).

PCs need the 3 letter extension at the end of a file name. Macs do not need a 3 letter extension at the end of a file name. If a filename in a PC does not have a 3 letter extension at the end, the PC doesn’t know which program to use to open the file. That’s bad!

So you look on your PC and you don’t see any 3 letter extensions at the end of any file names. Why? If you don’t see the 3 letter extension at the end of a file name, it’s because your PC has hidden the 3 letter extension (it’s still there though!). I like to be able to always see the extension at the end of a file name so that I immediately know what type of file it is and what program will open it.

You can choose to see the 3 letter extensions (like I do) by opening any folder. Then click on Tools in the menu bar. Then click on Folder Options. Then click on the View tab. Then remove the check mark from the box next to the line that says, “Hide file extensions for known file types.” That’s it – you’ll now see the file extensions at the end of each file name.

Speaking of 3 letter extensions - Did you know that a person using a Mac can send a Word file to a person who owns a PC. And the PC person can open it!! BUT - the trick is, the Mac person who sends a Word file to a PC person MUST add the 3 letter extension (.doc) to the name of the document in order for the PC person to open it. (Remember – the Mac doesn’t need the extension). Example: A Mac person sends a Word file called Wish List.doc to a PC person (Hmmm… that sounds familiar). Be sure to add the .doc to the filename so the PC person can open it. We do have some Mac people among us - so this is good to know!

If you are a PC person and send a Word document to a Mac person, you don’t have to put in the 3 letter extension – why? Because Macs are smarter than PCs. (Uh-Oh – I hope I don’t start another Mac/PC war!)

This works for any application that is made for both Macs and PCs – such as Photoshop and Excel. Also graphics like jpegs, gifs, and tifs can also be opened on both Macs and PCs - but the PC needs the extension.

Want to know what program a 3 letter extension belongs to – or want to learn more about file extensions? Check out this cool site. If it ain’t at this site, it ain’t anywhere! (Uh-Oh - that will never get by my spellchecker!)
http://www.icdatamaster.com/whatis.html

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