📘 Membrane computing is representing an active branch on natural computing. Membrane computing (also called P system) is mainly inspired from the functioning of the neural cells. In this book a historical survey of membrane computing is given, after that simulations of Boolean logic gates and basic database tasks using P system are represented, then a solution for the Rough P system problem is introduced, also how to apply the Rough P system to simulate the Boolean logic gates and basic database tasks is presented. Experimental Results show a comparison between the simulation of the two mentioned applications using the original P system and the Rough P system.