rcc is a command line tool included with Qt. Typically, the programmer does not interact directly with rcc. Instead, the project Makefile generated by qmake will specify the needed rcc actions for a given project.

rcc is the Qt resource compiler. It is used to used to embed resources into a Qt application during the build process, typically by processing project *.qrc files.

http://doc.trolltech.com/stable/rcc.html
http://doc.qt.nokia.com/stable/resources.html