This is very simple question but i don't think many people knows about that what is the difference between HTML and HTM why these both extension are different even both contain the same code style
Ans. Three letter extension (.htm) was due to Windows 8.3 filenaming convention used in DOS because it could not understand 4 letter extensions or long filenames. html is the proper extension and should always try to use this instead of htm. in 1995 when windows 95 arrived then it will give the support for more then 3 charcter extenshion thats why .html was drived always prefer to use ".html"
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