WordPress does not support a bilingual or multilingual blog out-of-the-box. There are however Plugins developed by the WordPress community which will allow you to create a multilingual blog easily.
Creating a mulitlingual blog is basically installing WordPress in more than one language and letting the Plugin switch between them. This includes installing .mo languages files which most Plugins will require you to do manually. See Installing WordPress in Your Language for details.
The free WPGlobus, Polylang, qTranslate-X, xili-language or Sublanguage plugins are installable on standalone WordPress sites. For multisite WordPress (one website per language), you can try Multisite Language Switcher, Zanto or Multilingual Press or purchase WPML.
WordPress started in 2003 with a single bit of code to enhance the typography of everyday writing and with fewer users than you can count on your fingers and toes. Since then it has grown to be the largest self-hosted blogging tool in the world, used on millions of sites and seen by tens of millions of people every day.
Everything you see here, from the documentation to the code itself, was created by and for the community. WordPress is an Open Source project, which means there are hundreds of people all over the world working on it. (More than most commercial platforms.) It also means you are free to use it for anything from your recipe site to a Fortune 500 web site without paying anyone a license fee and a number of other important freedoms.
On this site you can download and install a software script called WordPress. To do this you need a web host who meets the minimum requirements and a little time. WordPress is completely customizable and can be used for almost anything. There is also a service called WordPress.com which lets you get started with a new and free WordPress-based blog in seconds, but varies in several ways and is less flexible than the WordPress you download and install yourself.
What You Can Use WordPress For
WordPress started as just a blogging system, but has evolved to be used as full content management system and so much more through the thousands of plugins and widgets and themes, WordPress is limited only by your imagination. (And tech chops.)
You can transfer any blog or website from any service you wish. We have a list of guides which will help you to transfer from your specific platform.
The WordPress Codex has a Glossary where you can find definitions of many of the key phrases associated with WordPress.