First, are you on a Linux or Windows server? Windows servers (IIS) ignore the .htaccess file -- I believe there is a way to do URL rewriting, but I don't know enough about it to help you. If it's a Linux server (Apache), there are all sorts of things you can do with URL rewriting. Do you want your .php files to pretend to be another extension (e.g., .html), or do you want the extension to disappear completely? That is, if you have file /myfile.php, what do you want the world to see in the address -- /myfile.html or /myfile? The first is easy to do, and is very commonly done to hide the underlying site technology (more to allow you to change from .php to .aspx to .jsp to ... as the mood strikes you, without invalidating bookmarks and search engine indexes, than any kind of real security). The second is possible, but it can be a bit of a problem to keep directories (folders) from being treated as .php files missing their extensions. What are you looking to do? What kinds of things have you tried? If you're using a canned application, does it offer "SEO/SEF/Pretty URLs"?

Well, first you would change all your internal links to drop the ".php", e.g., <a href="/contact">Contact</a> instead of /contact.php (the file itself keeps its current name). Then you need to do something in .htaccess to invisibly map /contact to /contact.php.

The simplest way is simply to stick a ".php" extension on the end of anything that isn't already a valid directory or file, and doesn't already end with ".php". The following may work for you:

In the future, if you rename your files to something else (such as .aspx), you would change ".php" to ".aspx" in the .htaccess file.

You would have to also exclude .css files. Try this:

If you have other files, such as .js, you need to add them to the list.

thank you for the code which is so handy to me

@MrPhil - Please help me too.. 

I am using Linux Apache hosting (shared) of the other hosting company and all my files displays .PHP in url, I want to show them as .HTML

i tried many Rewrite codes inside my .htaccess file but they are not working.

Presently my  website URLs are in below patern, i want all of them to be .HTML in address bar.

http://www.mywebsite.com/about_us.php
http://www.mywebsite.com/contact_us.php
http://www.mywebsite.com/product_details.php?prod_id=385

PLEASE HELP..THANKS IN ADVANCE.

@avni111 you should always inquire with your hosting provider about such matters as there are different server configurations and obviously even if this is an open forum it would be hard for us to assist.

However if you would want to move to us so that we can provide full assistance you can always review our plans here: http://www.lpwebhosting.com/hosting/web