Shark is a C++ machine learning library. Tutorials and html documentation make Shark easy to learn. The installation of Shark is straightforward, it does not depend on any third party software and compiles under Linux, Solaris, MacOS, and Windows. Various example programs serve as starting points for own projects. Shark provides methods for linear and nonlinear optimization, in particular evolutionary and gradient-based algorithms. It comes with different types of artificial neural networks ranging from standard