# Potassco > [Potassco](https://potassco.org/), the Potsdam Answer Set Solving Collection, bundles tools for Answer Set Programming developed at the University of Potsdam. - [The Potassco Guide](https://github.com/potassco/guide) ## clingo > Current answer set solvers work on variable-free programs. Hence, a grounder is needed that, given an input program with first-order variables, computes an equivalent ground (variable-free) program. gringo is such a grounder. Its output can be processed further with clasp, claspfolio, or clingcon. > > [clingo](https://potassco.org/clingo/) combines both gringo and clasp into a monolithic system. This way it offers more control over the grounding and solving process than gringo and clasp can offer individually - e.g., incremental grounding and solving. - [Python module list](https://potassco.org/clingo/python-api/current/)