I dont think that this is the right explanation to such a good topic, I use Microsoft FrontPage XP, Dreamweaver and Nvu and all the three by default save the web page in the .HTM format and not .HTML. I dont think that these webpage edititors are lazy. There must be some hardcore reason behind all this other than the DOS and Unix problem.

Ok if it is for webpages, I can understand all that operating system differences, server problems and that lazy spoof. But what about that .jpg and .jpeg format of images, I dont think there is anyone who can answer this. It may sound really wierd but, I dont know why it is like this.

Some has to form a group or an organiztaion to set standards in extensions also.

Only old Minix systems that I am aware of (they were limited to 14 characters plus 3 character extension).

ganeshn11, the reason is they don't want tonnes of people calling them for support because their software that probably still runs on Windows 95, is not working because they can not use .html as an extension.

As I said, it was to make it compatible for these systems, but you should realise now that it's hardly likely that these are the systems you'll be running on anymore, plus if you know the reasons why .htm over .html, then you could easily adjust your editor to fix it, otherwise those who don't know, can just leave it as is, and hopefully it'd still work.

Editors cannot assume anything, and must work with the most compatible extension, which was the 3 letter extension because of limitations.

This is similar to XHTML extension, .xhtml or .xht and why it has a 3 letter extension, again limitation in some Operating Systems extensions (maybe until support is dropped for them will they move on). If there was no problems then they'd force people to not be lazy, as see .xht can be confusing to many, but seeing .xhtml a lot more people would understand what type of document it is, that way writing it in full is beneficial.


Cheers,


MC

Your right, FrontPage does still save web pages as *.htm by default

In my experience .htm and .html are treated the exact same, just like the guy above who mentioned .jpg and .jpeg

There is probably no right or wrong answer, but now im curious to put a index.htm and an index.html on my server and see which one is called wen you visit the main url

It would depend on your web server's configuration. Apache, for instance, has a configuration directive:
DirectoryIndex index.html index.htm index.php

With this configuration, Apache will first look for a file called index.html. If it can't find one, it will try to find index.htm. If it still can't find one, it tries index.php. But if they were in a different order, Apache would search for them in that order instead. I'd think most servers these days would have index.html before index.htm, but you never know.

As for .html vs .htm, who cares? I personally prefer .html, but I'm quite surprised at the number of people who consider .htm "not professional" and "lazy". It does exactly the same thing, so what's the problem? Most JPEG files are saved as .jpg, rather than .jpeg - is that unprofessional and lazy?

To be sure use html the server will just look at the first three or htm and if you use html will still work. Problem solved. Ha ha ha!

To answer the actual question, there is no difference between the two extentions. I mean there is absolutely no difference between the two extentions. In case you didn't understand what I was trying to say, there is no difference between the two file extentions.

Having made my point abundantly clear, I do have something to add.
Even though there is no difference between the two file extentions since the one is JUST a shorter version of the other or maybe one is JUST a longer version of the other, the longer version is preferable by todays standards which don't really mean too much since the only standard for web design is that there isn't any real standards.
There have been attampts to define standards but the browsers don't care, the browser developers don't care, and the web site designers don't care. This is because making a webste conform to the standards does not mean that all web browsers will correctly display the content nor does it mean that your page will be looked upon more favorably by the search engines or page ranking robots. In fact, trying to make your web site conform to the standards may make it more difficult to make it appear more uniformly accross all of the web browsers available.

I recommend that you use .html but whatever you choose to use, be sure to always use the same extention. This will reduce the number of dead or broken links on your web site.

vujsa

Between PHP, .asp, and Perl (.pl) it does not matter so much considering html is not used as often as it used to be.

Even if it is on most sites if you type in the domain ( www.whatever.com ) half the time it wont even show you what file your on until you click on a link inside the website.

I had heard as someone stated above. Some OS's back in the day could only see 3 letter extensions. Therefore it was .htm. Then when the new snazzy OS's came out they went ahead with .html which is a bit more appropriate.

I would also recommending .html, but its up to you. In my experience they are handled the same, but which does it load by default. If you have an index.htm, index.html, and index.php I guess it depends on ur server configuration. I know nothing of that =/.

The only use for the extension is for Windows to know what kind of file it is. So if you configure in Windows "xxx.bizzarreextension" to be evaluated as an HTML file it will have the same functionallity as xxx.html or xxx.html.

HTML files are just plain text files, wich text follow some rules to accomplish the w3c recommendation for Hypertext Meta Language.

The 3 character extension is due to the 8.3 file name format on some old sistems like MSDOS