File extensions
August 18th, 2008Computer Bytes No. 27
Ever wonder about those letters that come right after the ‘dot’ at the end of a file name. These two, three and four letter extensions define the type of file. The File Name can be anything you or the person that created the file chooses, usually a name that will remind you of the contents. However, the assigned file extension tells the computer what type of file it is and which program to use to open it. Most files fall into basic categories such as execution-application, text or word document, graphic, spreadsheet, web files and zip.
The following are some of the more common file extensions. EXE is an executable or application file and is executable or self-extracting by double clicking. If you receive an EXE file as an attachment to an email, open with caution as this is a favorite method for sending viruses. Word processing and text programs such as Word Pad have extensions such as DOC or TXT. Word pad documents will not run in a word processing program and word processing documents will not run in word pad, and trying to do so may cause you to compromise the format and content of the document.
Graphic programs offer a variety of extensions that may show the number of colors, format and how the file is managed through the graphics program. The more recognizable file extensions for graphics are GIF (Graphic Interface Format), JPG (Joint Photographers Group), TIFF (Tagged Image File Format) and BMP (Bit-mapped Graphic Photo).
Spreadsheet files may end in XLS which is the extension used by Excel. Other spreadsheet programs may have their own unique extensions. There are many file extensions for the pages uploaded to the Internet. These extensions let you know what type of page you are viewing be it text, audio, video or something else. An HTML extension (Hyper Text Markup Language) is typical of most text pages. Pages that have a PHP extension (originally Personal Home Page) is a page containing a server-side script that performs a function. There are other embedded program extensions in web pages that will allow them to perform a wide assortment of functions from Email Forms (CGI), Cascading Style Sheets (CSS), Java (JS) and Perl (PL).
An extension you probably have seen if you have viewed an on line manual is PDF (Portable Document Format). You must have a special program - Adobe Acrobat Reader - installed in your computer to view PDF files. These files may include text, fonts, images and graphics which make it perfect for on line manuals and instructions. If you want to send a large file quickly use WinZip or PKZip to compress the file. This will result in a ZIP extension.
If you are unsure of a file’s extension and the correct program to use to open it, you can enable the viewing of File Extensions on your computer. Doing this will allow you to view the file extension making it easier to select the correct program for use. There are many more file extensions and should you care to look further into this topic perform a search on Google or Yahoo for ‘common file extensions’.
This article prepared courtesy of MoncriefWebDesign.com…