Difference Between HTM and HTML

HTM and HTML refer to file extensions of HTML files. They are files of a plain text type. HTML stands for Hyper Text Markup Language, which is a markup language used for creating web pages. HTML actually uses markup tags for describing web pages. As file extensions, they are denoted as .htm or .html. If you use HTML files to create your web page, then an .html or .htm will most likely appear at the end of its URL. Here are examples: ‘http://code.google.com/chrome/extensions/samples.html’ and ‘http://edgewisdom.com/Finance1.htm’.

TM is used only as an alternate extension to .HTML. This happens for some reasons, for example, in some operating systems, like the Disk Operating System and Window 3.X, they do not allow the use of four-letter extensions. Therefore, instead of .html they use .htm. As well as in the world of windows, three-letter extensions are most commonly used, like ‘.doc’ and ‘.exe’, therefore, .htm is more applicable here. However, there are also some cases, with other server’s, when they create their default directory to only support .html files. So it means .htm is not allowed on that server.

In actual fact, .htm was usually used back in the old days, like during the time when DOS was popular. In the present time, computers can now easily support big files and wide length of file names, therefore, having a four-letter extension is not a problem anymore.

Anyway, file extensions are useful to operating systems because it helps them identify what type of data file they are dealing with, and also so that they can find an appropriate program to read or edit it. If your computer is unable to open the files, especially files with unknown file extensions, it means that you may not have the associated program installed to be able to read it, or you may have windows registry errors related to the file extensions.

In the case of the internet, web browsers do not really see the file extensions, so when you type a URL with no HTM or HTML extension, the browser can still find the source, and display its contents. HTM and HTML are only two of the thousands of types of file extensions. Although, HTML is the most common web page format used, and that’s why they are more popular.

Summary:

HTM and HTML are both file extensions of HTML files. The only difference is that .HTM is used as an alternate to .HTML for some operating systems and servers that do not accept four-letter extensions. Although today, operating systems have developed, and can now support long file names and four-letter file extensions.