Extensions: - What's in a Name?
By DIANE MCCARGAR
The next time you look at a file on your computer and wonder what it is and where it came from, try looking for an extension. Many file names end with an extension, a dot followed by 2 to 4 letters (e.g. letter.doc). Most Windows programs automatically add extensions to file names. These letters can tell you the type of data contained in a file and sometimes they identify what program was used to create it. They may also tell you the version of the program. If you know what software was used to create a file and your computer has this software, then viewing its contents becomes very simple - run the program and then open the file. If your computer doesn't contain the software or you don't know what software was used, then double-click on the file and see what happens. If the computer can't find or doesn't recognize what program the file came from, then it will ask you to choose from a list of software installed on your computer. Extensions can help you choose the most appropriate software to view a file. Here are some common file extensions:
Email and the Internet have made it common place for people to share documents. If you have tried to do this in the past, you probably realize how many problems can occur. Maybe, you weren't able to view something because you didn't have the same software or you had an older version of the software. Maybe you could view it, but the text and graphics weren't formatted the way they should be. A new file type called Portable Document Format (PDF) tries to overcome this problem. PDF files are formatted so that they can be viewed and printed the same way on any computer using Adobe Acrobat Reader. Anyone can download Adobe Acrobat Reader free of charge from Adobe's Web site: http://www.adobe.com. Additional software from Adobe is needed to create and edit PDF files. PDF is now becoming the standard format for posting document files on the Internet
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