What is Xtext?

XText is a language development framwwork supported by Eclipse.You can create a small textual domain-specific language (DSL) or a full-blown general purpose programming language in a very short time.

XText can also be used to create an Eclipse-based development environment.

XText is an example of how  the lightweight dependency injection (DI) framework Google Guice is used to wire up the language and the IDE infrastructure.

XText is used for code generator, game developementn etc. Xtext-based languages is used to drive code generators that target Java, C, C++, C#, Objective C, Python, or Ruby code.
XText can be used instead of XML. XText is a very powerfil tool, if you use it correct, you will make the life far easy for many developers.