URL reqriting is Simple Rewriting Your URLS (links) Also Redirecting Them To Known URLS.e.g you’ll make the link :

view_my_profile.html –> Is Redirected to function.php?op=3

so instead of the link “function.php?op=3″ Which isn’t enough describing itself we’ll make the link “view_my_profile.html” Which is very describtive.Why using mod_reqrite?. Now see if your site has more than 10,000 Links (Dynamic Website) , do you think we would make 10,000 html files ??

=>Of course Not , and here’s the Use Of Mod-Rewrite. We can achive dynamic pages from code and rewrite their URL using this module.

=>well simply This is Very very useful for search Engines to correctly index Your website and gather keywords, we'll talk about this in details in "Search Engine Optimization Tips"

How to Enable Mod_rewrite:-
how to configure mod_reqrite to work It Depends On Your Operating System (Server's Software) .

* For Linux It's Supported By Default (in Most Of The Servers) - ModRewrite Is An Apache Module You Don't Have To Setup Anything And We wont Go On How To Install The Mod-Rewrite On Your Linux Server Cause It's little Advanced And Complicated.However you can have mod_rewrite module loaded in apache.
* For windows : A lot of developers think that it's not supported by windows server but infact it is.I'll Describe How You Can Set it Up On windows (Assuming That You Have IIS installed On Your PC/Server).But If You Haven't Then You Can Refer To This Post: showthread.php?t=1 (http://www.phpegypt.net/forum/showthread.php?t=1)
o For Windows XP / 2003 Server
+ You Must Download The Files From ( http://www.iismods.com/download.htm ) also I Attached It to This Post .. [It's Free Released under the GNU General Public License (v2)](May be this link is not working sometimes.)
+ Place It Somewhere on your H.D.D let's Say "c:\mod_rewrite"
+ Goto Control Panel -> Administrative Tools -> Internet Information Services
+ You'll Find Your Computer name And bet ween 2 Brackets (localhost) Click it -> open "Web Sites" -> "Default Website".
+ Right click on "Default Website" Choose "properties".
+ You'll Find Many Tabs At The Top Click "ISAPI Filters".
+ Click Add, Enter "MOD_REWRITE" As The filert name And For The executable Click "Browse" And Choose The file "c:\mod_rewrite\mod_rewrite.dll" or just choose The file "mod_rewrite.dll" Which You Extracted In The Desired

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