Without search engine optimization many websites stand the chance of not being fully indexed by search spiders therefore risking not being ranked high enough (if at all) in the search engine results pages (SERPs). The resulting poor conversion rate makes the website a dead weight, demoralizes your staff and could threaten your business.
This situation is quite easy to avoid by performing some cosmetic operations to the site. One of these operations, URL rewriting, is considered by some rather difficult and a bit time-consuming but can be extremely effective and rewarding in the long run.
Why It Is Nice to Have Clean URL'sThere are two very strong reasons for you to rewrite your URLs, the first of which is related to Search Engine Optimization. Search engines are much more at ease with URLs that don't contain long query strings.A URL like http://www.example.com/4/basic.html can be indexed very easily whereas its dynamic form, http://www.example.com/cgi-bin/gen.pl?id=4&view=basic, can potentially confuse search engines and cause them to miss important information contained in the URL and you to miss those anticipated high rankings.With clean URLs, the search engines can distinguish folder names and can establish real links to keywords. Query string parameters continue to be an impediment in many search engine's attempts to fully index sites. Several SEO professionals agree that dynamic (or, dirty) URLs are not very appealing to web spiders, while static URLs have greater visibility in their electronic eyes.
The second strong reason for URL rewriting would be the increased usability for web users and "maintainability" for webmasters. Clean URLs are much easier to remember. A regular web surfer will not remember a URL full of parameters, and would obviously be discouraged by the idea of typing the entire URL. This is less prone to happen with clean URLs. Easily remembered URLs help you create a more intuitive Web site and make it easier for your visitors to anticipate where they can find information they need.Webmasters tend to find that maintaining static URLs is a much easier task than working with dynamic ones. Static URLs are more abstract, and thus more difficult to hack. The dynamic URLs are more transparent, allowing possible hackers to see the technology used to build them and thus facilitating attacks.Also, given the length of dynamic URLs, it is very possible for webmasters to make mistakes during maintenance sessions, resulting in broken links. Also, when static URLs are used, the links to the site's pages will still remain valid should it be necessary to migrate a site from one programming language to another (e.g. from Perl to Java).
Dashes vs. UnderscoresWebsites that still use underscores for their URLs are becoming scarcer and scarcer. Some say that people who still use underscores are "old school" while dashes seem be used far more often these days.A usability related reason for using dashes rather than underscores is the elimination of the confusion created between a space and an underscore when the URL is viewed as a link, or when printing such a URL.More to the point, the chances that a combination of keywords contained in your Web site is included in the SERPs increase exponentially when using dashes.For exemple: a URL that contains "seo_techniques" will be shown by the search engine only if the user searches for seo_techniques (this kind of search is rarely performed); whereas searches for "seo", "techniques", or "seo techniques" gives your URL containing "seo-techniques" a better chance of being displayed on the SERPs. The dash will help you more than you can imagine, by greatly improving your visibility on the Web.
How to Rewrite URLs
The principle of URL rewriting is actually setting a "system" on the host server that will allow it (the server) to know how to interpret the new URL format. What actually happens when one decides to rewrite the URLs of a website is called masking the dynamic URLs with static ones. This means that the URLs that previously contained query strings with elements such as "?", "+", "&", "$", "=", or "%" will contain the more search engine friendly "/" (slash) element, presenting themselves in a simplified form.To help you with cleaning your URLs here are some rewriting tools and engines, some free of charge, others fee based.
Online / Open Source Tools
free online URL rewriting
open Source URL Rewriter for .NET / IIS / ASP.NET
open Source rewrite-module tuned for ASP.NET 2.0
mod_rewrite This is the most common non-fee-based rewriting engine. It is a module from the Apache HTTP Server that allows the easy manipulation of URLs. The use of this module requires the enabling of the RewriteEngine on your Apache server. Then, rewrite rules must be defined, (you can even set conditions for each rule), thus allowing the rewrite requests as they come in.In terms of SEO, mod_rewrite can be helpful if you have complex URLs that contain more than 2 parameters. In other words, if one of your dynamic URLs is accessed, the mechanism behind mod_rewrite will "translate" it into a shorter, friendlier, static-looking URL.
ISAPI_RewriteThe Internet Server Application Program Interface (ISAPI) is another URL manipulation engine that functions in a similar way to Apache's mod_rewrite, the difference being it is designed specifically for Microsoft's IIS (Internet Information Server).
IISRewriteIISRewrite is a stripped down implementation of Apache's mod_rewrite modules for IIS. It is a rule-based rewriting engine that allows a Webmaster to manipulate URLs on the fly in IIS.
URL ExamplesHere are some examples of how URLs can look before and after rewriting:Example 1:
Dynamic URL: http://www.companyname.com/products/items.php?id=x&model=y&variety=z (before rewriting)
Static URL: http://www.companyname.com/x/y/z.html (after rewriting) Example 2:
Dynamic URL: http://www.example.com/cgi-bin/gen.pl?id=4&view=basic (before writing)
Static URL: http://www.example.com/4/basic.html (after writing)
ConclusionsURL rewriting can put you on the right track in the race for high organic rankings when combined with other SEO techniques. Be aware that rewritten (and, presumably, better looking and more effective in terms of search engine ranking) URLs cannot substitute or make up for a poorly designed Web site.Don't expect miracles. Nevertheless, when you decide that your site needs a makeover and start rewriting your URLs, make sure that:
You keep them as short as possible (to increase usability),
You use dashes rather than underscores (to give your site a better chance of ranking as high as possible in the SERPs),
You use lowercase letters rather than uppercase ones (to avoid those case sensitive situations),
The technology you have used cannot be detected in any of your URLs (to prevent possible hacker attacks).