Programmable Logic Controller (PLC) which can handle the binary input and output of logic statement which are saved in its memory. Its a digitally OS which are logically stored in its memory by the programming system.
Distributed Control System (DCS) is a computerized control system for a plant or process usually with a multiple number of control loops, in which autonomous controllers are distributed all over the system.

DCS is a powerful platform for both modulating logic and Boolean logic. A DCS can handle many functions previously thought more appropriate for PLCs.
PLCs are good at Boolean logic. PLC – Programmable logic controllers have the capabilities once found only in distributed control systems DCSs,