A descriptive URL does exactly what it says on the tin, it describes what a website is about in the URL itself for example:
In the example above the URL clearly indicates to the visitor that they will be viewing a page about descriptive URLs. They are similar to static URLs but have the added benefit of using keywords associated with the webpage in the name of the URL, which is very good for SEO purposes.
Descriptive URLs are encouraged for the following reasons:
Lastly when it comes to social media and link sharing a descriptive URL is very important because link shortening for Twitter can eradicate what a URL stands for. Therefore having a descriptive URL can that pops up when they hover over a shortened link can encourage click-throughs.
Keyword Assessment | Meta Data | Webmaster Tools | Google Analytics | Monthly Reporting | Robots.txt | .htaccess | Favicon | Site Map | Search Engines | Google Maps | Forms and E-mails | Footer Link | Google Search Engine | Picture Tagging | Directory Page | Social Media | Heading Tags | Indexed Pages | Robots | Sitemap | HTML Errors | Search Engine Errors | Broken Links | Pages and Content | Search Engines | Picture Tagging | Flash and iFrames | Hierarchy | Forms and Emails | Add Media | Static URLs | Descriptive URLs | Duplicate Content | Plagiarism Check | Positive Content | Negative Content | Character Coding | Downloadable Files | Optimize Graphics | Optimize Navigation | Incoming Links | Outgoing Links | Page Content | Meta Data | Rich Content | Reduce Bounce Rate | Social Media | Analyze Competitors | Website Security | 3rd Party Tracking