Possible Duplicate:
.htm vs .html
What is the difference between .html and .htm file extension in a Basic Web Page?
views:
121answers:
7
+2
A:
There is none. HTM is the shorted version invented by microsoft for their old 8+3 file format, where each file could have only 8 characters in the filename and three in the extension.
ZeissS
2010-06-13 10:35:15
@ZeissS: 3 character file extensions did not originate with Microsoft.
John Saunders
2010-06-13 10:57:53
+8
A:
None. I believe .htm to exist only due to the MS DOS limitation of 3 characters for file extension, which then propagated as a bad habit to early windows versions and programs.
Miguel Ventura
2010-06-13 10:35:49
@John: No, but Microsoft's MS-DOS certainly made three character extensions infamous! Besides, HTML did not even exist when operating systems that predated MS-DOS (such as CP/M) were popular.
Derek Mahar
2010-06-13 12:31:57
@Miguel: sufficiently infamous for people to forget their history and think that History started with MS-DOS. It didn't. There were reasons why MS-DOS used 8+3. It was copying several earlier small OS's. CP/M for one, but then CP/M copied earlier systems, some of which also used "PIP" to copy files.
John Saunders
2010-06-13 13:13:32
@John, I think you meant @Derek :) Still, I'm not blaming Microsoft on anything. I was just referring the MS-DOS limitation that propagated to Windows' early versions because I believe it to be the most influential regarding this issue. Most other 8.3 systems never got to taste the dawn of the interwebs.
Miguel Ventura
2010-06-13 13:44:13
Good find. I was about to chastise you for making this an answer rather than a comment, but I see that you did not have that option at the time. Now you have the power to comment on arbitrary posts, so please put future duplicate calls in the comments.
dmckee
2010-06-13 20:34:44
+1
A:
Whether a URL refers to an HTML page or not depends on the server's content-type not on its file extension. For instance htpp://www.google.com/ returns HTML even though no .htm or .html can be seen. You could even configure your web server to make this URL: http://my.server.com/foo.jpg return HTML instead of a JPEG image. As far as URLs are concerned file extensions do not have any meaning.
Erik
2010-06-13 11:26:13
A:
Basically, None.
.htm used to be normal when the length of the extension was important (in the days of 8.3 letter filenames) but that has not been an issue for a long time and .html is more common today since it is more descriptive.
So far as the web is concerned, you can use any extension you like or none at all (so long as the server is configured to send the right mime-type) - the extension is only an issue on your local computer.
caesarsgrunt
2010-06-13 12:49:52