Membrane Computing is an emergent branch of Natural Computing introduced by G. Paun. This new model of computation starts from the assumption that the processes taking place in the compartmental structure of a living cell can be interpreted as computations. The devices of this model are called P systems. Roughly speaking, a P system consists of a cell-like membrane structure, in the compartments of which one places multisets of objects which evolve according to given rules.

    Most variants of membrane systems have been proved to be computationally complete, that is equivalent in power to Turing machines, and computationally efficient, that is able to solve
computationally hard problems in polynomial time. Although most research in P systems concentrates on computational powers, lately they have been used to model biological phenomena.

    As P systems are inspired from the structure and functioning of the living cell, it is natural to consider them as modelling tools for biological systems, within the framework of Systems Biology, being an alternative and complementary to more classical approaches like Ordinary Differential Equations (ODEs) and to some recent approaches like Petri nets and π-calculus.

    P system models take into consideration the discrete character of the quantity of components and the inherently randomness in biological phenomena. Besides, the key feature of P systems is the so called membrane structure which represents the heterogeneity of the structural organisation of the cells, and where one can take into account the role played by membranes in the functioning of the system.

The site has been produced by John Auld, Francisco Romero-Campero, Marian Gheorghe.