QT what is it?

Over my years of study & work I have been programming on x86 under the following OS windows and Linux (Ubutnu the well known Debian Linux distribution). Usually I have been using on windows Microsoft Visual Studio as the IDE of choice, and on Linux Kdevelop/Code::block/netbeans.
But what bothered me most was writing software to both OS’s, I found it difficult to interact between the two. till I heard about QT SDK.
QT(platform), which is pronounce cute. It’s belong to Nokia, actually to be more precise one of Nokia’s acquisition on 2008 was a Norwegian company called Trolltech, which built it from scratch.
QT is free and open source, it fully supports C++. the nice fact about QT is, all editions support a wide range of compilers, including of course the well known GCC c++ compiler Visual studio suite. The fact being a cross platform makes it great for future developing! J
It astonished me how well documented all the the QT objects are, great examples which make sure you understand in depth every topic. I’m very familiar with the STL (Sample Template Library), but I found out that QT library provides a set of container classes.