WordPress actually is a platform for blogging. When the first time WordPress was created, it was just a platform where people can write blogs. WordPress was created in 2003 when a lot of people wanted to write blogs and then of course WordPress was changed so that we can build some websites as well. So, now, these days you can build a very sophisticated website. That is basically what WordPress is. It is an online application which is used primarily for blogging or also for building websites.
WordPress is built using PHP which is an open source server side language similar to ASP.Net of Microsoft. PHP uses MySQL, an open source relational database management system. WordPress is built upon these two technologies – PHP and MySQL.
History of WordPress – WordPress was started in 2003 by Matt Mullenweg and there were Michael Valdrighi and Mike Little who also worked on. It is available under Free GPL License whcih means GNU Public License which is open source. It means that you can download the source code but if you modify the source code, then you have to make that modified source code available to the whole world.