Dynamic and static are the two types of URLs at present. Static URLs are in general ranked better in search engines and they are indexed more promptly than dynamic URLs. Google finds static URLs more comfortable since it assumes a dynamic looking site is far too large and slows the crawl speed. Now Google claims it can crawl dynamic URLs.

During earlier times, all websites used static HTML pages and so the first search engines were oriented towards static web pages. As the web technology developed several new methods to generate websites and dynamically generated web pages came into being. Dynamic web pages differ from static pages in that there is no physical equivalent to the page you may be viewing on the server. Dynamically generated pages are mostly based on a single template page for generating an entire website. Since dynamic pages use scripting languages like PHP and ASP, they came to acquire the language names like dynamic-page.php.

Sample Static page: http://www.searchenginegenie.com/search-engine-optimization-articles.htm

Sample Dynamic Page: http://www.searchenginegenie.com/search-events/view_entry.php?id=717&date=20090803

Dynamic URLs versus static URLs has for long been a hotly debated subject among webmasters. A static URL, simply stated, is one that does not change and therefore does not contain any URL parameters. The fact is updating these kinds of web pages can be tedious as every single page has to be hard-coded. This is the reason why webmasters who have to frequently update sites like online shops, forum communities, and blogs or content management systems prefer to use dynamic URLs. It is recommended that if you want to serve a static URL, you should create a static equivalent of your content.

Dynamic URLs are generally used if the content of a site is stored in a database and pulled for display on pages on demand. In such cases, the site serves more as a template for the content. But it is said that URLs have a distinct disadvantage in that different URLs can carry the same content.

A simple example would be a 1000000 page site with each page generated with the format below

http://fishbase.org/Country/CountrySpeciesSummary.cfm?c_code=356&id=24516
http://fishbase.org/Country/CountrySpeciesSummary.cfm?c_code=356&id=24517
http://fishbase.org/Country/CountrySpeciesSummary.cfm?c_code=356&id=24518
http://fishbase.org/Country/CountrySpeciesSummary.cfm?c_code=356&id=24519
http://fishbase.org/Country/CountrySpeciesSummary.cfm?c_code=356&id=24520
http://fishbase.org/Country/CountrySpeciesSummary.cfm?c_code=356&id=24521......

All the above mentioned six URLs end up with six different landing pages. But when the search engine tends to remove the information subsequent to the first offending character, the question mark (?), ultimately all the six pages become identical :

http://fishbase.org/Country/CountrySpeciesSummary.cfm
http://fishbase.org/Country/CountrySpeciesSummary.cfm
http://fishbase.org/Country/CountrySpeciesSummary.cfm
http://fishbase.org/Country/CountrySpeciesSummary.cfm
http://fishbase.org/Country/CountrySpeciesSummary.cfm
http://fishbase.org/Country/CountrySpeciesSummary.cfm

At this instant, your unique pages have become identical, and consequently the URL's are duplicated which won't be indexed by the search engines.

This is one foremost reason why webmasters prefers to rewrite their URLs and make them as static ones. But while rewriting URLs, it must be borne in mind that it is tough to correctly generate and maintain rewrites. Professional's suggestion is that while rewriting the URL it is necessary that you remove the redundant parameters while maintaining a dynamic-looking URL.

Here's an example of a URL with a couple of parameters:

http://fishbase.org/Country/CountryChecklist.php?c_code=356&vhabitat=fresh&sid=98ert17890664

c_code indicates : Country code

vhabitat indicates : Type of fish category

sid=98ert17890664 - the session ID number is 98ert17890664

The following are some examples of static-looking URLs which may cause more crawling problems than serving the dynamic URL without rewriting:

Dynamic URL : http://fishbase.org/Country/CountryChecklist.php?c_code=356&vhabitat=fresh&sid=98ert17890664

Wrong URL Format 1 : http://fishbase.org/Country/CountryChecklist-c_code-356-vhabitat-fresh-sid-98ert17890664.html

Wrong URL Format 2 : http://fishbase.org/Country/CountryChecklist//356/fresh/98ert17890664

Wrong URL Format 3 : http://fishbase.org/Country/CountryChecklist,356,fresh,98ert17890664.html

Wrong URL Format 4 : http://fishbase.org/Country/CountryChecklist-356-fresh-98ert17890664.html

Rewriting your dynamic URL to one of the above examples might cause us to crawl the same piece of the content unnecessarily through many different URLs with varying values for session IDs (sid). These forms make it difficult for us to understand 98ert17890664 have nothing to do with the authentic content which is returned through this URL. Conversely, here's an example of a rewrite where all irrelevant parameters have been removed:

Correct URL Format (After Rewriting the Dynamic URL) : http://fishbase.org/Country/CountryChecklist//356/fresh

consequently the finest solution is to keep your dynamic URLs as they are. Or, if you tend to remove irrelevant parameters, bear in mind to leave the URL dynamic as the above example of a rewritten URL shows:

Correct URL Format (Dynamic URL) : http://fishbase.org/Country/CountryChecklist.php?c_code=356&vhabitat=fresh

How to Rewrite Dynamic URL's

Mod Rewrite Rule Generator tools helps you to generate dynamic URLs to search engine friendly URLs. For search engine friendly (rewrited) URLs you need the rights to put a .htaccess file on your webspace and you need the Apache Webserver module mod_rewrite. Check it [http://www.searchenginegenie.com/mod-rewrite-generator.php].

Sample Code
Dynamic URL : http://fishbase.org/Country/CountryChecklist.php?c_code=356&vhabitat=fresh

.htaccess Code:

RewriteEngine on

RewriteRule ^CountryChecklist-(.*)-(.*)\.html$ CountryChecklist.php?c_code=$1&vhabitat=$2&sid=$3

Generated URL : http://fishbase.org/Country/CountryChecklist-356-fresh.html

Go excavate and start learning the Mod Rewrite in detail.[http://www.webforgers.net/mod-rewrite/].

There is a popular misconception that dynamic URLs cannot be crawled. Google claims it can crawl dynamic URLs and interpret the different parameters. Google may have problems crawling and ranking the dynamic URLs if dynamic URLs are made to look static and parameters hidden. Thus the inference is to avoid reformatting a dynamic URL to make it look static. It is preferable to use static content with static URLs as far as possible. But in the event webmasters decide to use dynamic content, they should provide the possibility to analyze the URL structure by not hiding parameters and making them look static.

As you can see the HTML version is the best because it is so easy to manipulate and the dynamic URLs can at times be atrocious. Google has however made it amply clear that dynamic sites cannot be crawled as fast as static sites. Google is apprehensive that dynamically generated sites can potentially have unlimited pages and so Google assumes a dynamic looking site is far too large and slows the crawl speed.

It is good to know that if you are starting a new site and want the most traffic out of Google, then filenames are important and static HTML pages are very easy to name for optimum SEO benefit. Google finds static URLs more comfortable because Google takes all words it recognizes from a URL and uses that in the rankings algorithm.

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