Cilk, Cilk++ and Cilk Plus are general-purpose programming languages designed for multithreaded parallel computing. They are based on the C and C++ programming languages and extend these with constructs to express parallel loops and the fork–join idiom.Originally developed in the 1990s at the Massachusetts Institute of Technology (MIT) in the group of Charles E. Leiserson, Cilk was later commercialized as Cilk++ by a spinoff company, Cilk Arts.