Many Qt modules are offered with two different APIs; one for QML and one for C++. While I can take for granted that you know enough about the C++ language and how to work with it, the same may not be true for QML, which is a language that was born in and is mostly used within the Qt world.
You may hear sooner or later that QML is the language used for building modern UIs with Qt. Although that is certainly true, this often implies to many that QML is only good for implementing UIs. That's not the case, although you should always carefully think what kind of API (C++ or QML) is best suited for the project or the component at hand.
QML is a declarative language, which, on one hand, supports JavaScript ...
