WordPress saw its initial release in May 2003 and quickly became one of world's most popular open-source content management system. Its closest rival is Joomla, that CMS is used by 3.1 percent of all websites.
WordPress' success can be attributed to its ease of use and extensibility. The tool takes mere minutes to learn and allows plug-ins that make it very customisable. And with 30 per cent market share, developers would be foolish if they ignore the platform.Via: The Register