The behavior of systems with this property is modeled using the pi-calculus, which Milner, Parrow, and Walker put on a more rigorous (10[1])algebraic footing than Carl Hewitt’s Actor formalism. Per Brinch Hansen developed a version of Pascal for writing programs with this property based on constructs called monitors that were first theorized by Hansen and Tony Hoare. (10[1])When designing systems with this property, (10[1])an MPI implementation, OpenMP, (10[1])or some combination of the two (10[1])are used for communication. (10[2])Proving the correctness of programs with this property (10[2])requires proving safety and (10[1])liveness (10[1])properties. (10[1])To enable writing programs with this property, high-level languages provide atomic classes. The dining philosophers (10[1])problem (10[2])illustrates how (10[1])systems with this property can enter deadlock. For 10 points, (10[2])name this property possessed by systems that perform multiple computations (10[2])at the same time. (10[3])■END■ (10[1])