If your domain URL contains characters such as: £ % $ & = etc then search engines would find it difficult to read them. As these characters are 'dynamic' in nature and are actually commands in their own right and if you include them in the URL it confuses search spiders.

In the past, websites normally used to have less than a hundred pages, since they were not much used for ecommerce. However as business over the internet grew, every shopping portal had to manage thousands of products. The easier and better manageable methodology was to keep all of the products in a database and use a webpage template and dynamically load products into it as and when a user request is encountered.

This approach leads to the usage of URLs to pass product/customer specific information to ensure the user is navigated to the appropriate product information.

A typical dynamic URL would look like this:

http://www.mysamplewebsite.com/Mountings.aspx?req=268&c=4565d-d59

Technically it helps a webmaster to manage the web pages easily, however for search engine spiders this has proved to be a tedious task, since they are unsure as to how to navigate using dynamics, hence skip most of such pages.

Ideally, the entire URL needs to be readable and meaningful to a human eye. That by itself would ensure readability to search engines, and they know what the URL has in stock for the user.

I would suggest keeping URLs similar to what you see below:

http://www .mysamplewebsite.com/article/myarticle1

http://www .mysamplewebsite.com/submission

http://www .mysamplewebsite.com/product1

http://www .mysamplewebsite.com/product2

It's a known fact that search engine friendly static URLs are indexed more effectively than complicated database-driven dynamic URLs.

Yet another difficulty in using dynamic URLs is while sharing links of specific product pages to contacts and during link building. The URLs become un-manageable and stand a high chance of resulting in broken links.

Having all this said, how can a webmaster manage to still keep all his products showcased on the websites while maintaining clean URLs?

That's where URL Rewriting comes into picture!

There are tools available which can be used by a website developer, with which the dynamic URLs when requested for can be masked with static ones while displaying the web page. That means in the background all the query parameters can still be passed, whereas the URL presented would show a clean static one.

So a URL like this,

http://www .mysamplewebsite.com/Mountings.aspx?req=a178&cc=4523e65d-ba8e-1644539c79bf

after undergoing the URL Rewriting process would reach a Search spider / Web user as,

http://www .mysamplewebsite.com/product1

Now days every dynamic websites are busy getting their URL's converted with Rewriting tools to ensure better visibility on search engines.

Though many search engines now claim that there search spiders have now overcome the difficulty in parsing dynamic URLs, I still know a lot of websites that use dynamic URLs and gets less than 300 of their web pages visible to Google; in reality they contain at least 4000 product pages!