Many applications and application frameworks are developed using the C or C++ programming languages. According to the TIOBE index these languages are part of the top 3 most popular.
The document Develop with C describes how you get started with application development using the C programming language. The document contains instructions of how to build and install a toolchain as well as build and run the application on the target.
Besides the toolchain it is also important to setup a development environment and more specifically an editor. The document contains instructions of how to install and use Eclipse.