Control system is included in operating system and usually in each application as well. It should be striven for as much system and as little application control as possible.

Control system should take care for decentralized system modules coordination (interaction) and should not influence an application.

Task - various operations that have to be completed in order to fulfill a request from user or some system resource.

Sub task - operation or various operations that provide partial results for a master task.

Operation - semantically closed processing that provides partial results for a sub task. Results are in a syntactical non readable form for end user.

Function - segment that doesn't have user oriented purpose and which results are not usable for end user.

Control system types

C0 - central control

Basic type with only one central supervisor that controls and coordinates all tasks. This type is used rarely today.

C1 - static control master - slave

Simplest type of decentralized control system. Supervisors are related in hierarchical order - master/slave. Relation is static ie. one supervisor is always master to other and the other way around.

C2 - dynamic control master - slave

There is a hierarchical relation between supervisors that can change over time.
For example: When communication channel is established between two nodes the node requesting connection always becomes master. And only master can close the connection. The other node is slave. When the connection is closed the second node may request new connection and roles of the two switch.

C0, C1 and C2 are typical for single computer systems and simple applications in multiple computer systems.

C3 - application control system

Sub-task execution is controlled by application segment that incorporates their results in end result. System supervisors are completely autonomous. Among segments control principles C1 or C2 can be valid.
For example user program with subprograms that can be run on different computers.

C4 - function control system

Some functions are controlled by a system. This type comes handy because application code for single and multi user environment can be the same.
For example DBMS (wiki) that controls access sequence when more users want to change same data simultaneous.

C5 - operation control system

System control on operation level (operation includes more functions). Connections between task and sub-tasks have to be integrated.

C6 - homogeneous sub-task control system

Control on sub-task level that can choose between available systems for processing (systems are the same type).

C7 - autonomously cooperative task control system

Each computer is autonomous in decision whether to process sub-task or give it to other computer to process.

C8 - transparent control system 

User is not required to have any knowledge about task it is enough to make proper request to the system. Structure and architecture of system is completely transparent to end user.