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What Are File Extensions? - Part 3

Aside from the benefit it provides to computer systems, file systems are beneficial for us users. By merely looking at the properties of the file where the file extension can be seen, we can immediately figure out what type of applications we need to open it. Similar to what Windows do, if a file you opened does not associate any installed application on a system, it will prompt you if you want to look for compatible applications through the Internet.

Though with the help of file extensions a file can be rendered by similar applications that created it, there are instances when this does not work. And that is for cases referred to as backwards compatibility. Applications are upgraded to fix bugs and meet future demands. The process of upgrading an application may some times remove its ability to render files created with an earlier version. Microsoft Word 2007 produces a different type of document than its predecessor. It appends the *.docx file extensions which is unreadable to older Microsoft Word applications. This requires the compatibility software to be installed to resolve this limitation.

Some applications are also designed to render multiple file extensions. This means that aside from the default file extension it creates, it can also open and execute other file extensions related to it. Popular examples are the WYSIWYG (What You See Is What You Get) applications that are used to design objects found on the Internet. Aside from the default *.html extension it create, WYSIWYG's can also open and execute files with extensions *.php, *.asp, *.aspx, *.htm, *.html, *.jsp, and other extensions used to run web pages.

Without the presence of file extensions, computers will be having issues in associating files with applications. To simplify the complex nature of file extension, we can say that these are suffixes associated with a specific application that can execute a file. So if you have a file labeled "text.doc", then it is not in any way associated to the file "text.odt". As long as you have file extensions that make your filename unique to the application that created it, the file will never be in conflict with other files of the same filename.