Degree Of Control of System
Centralization and Decentralization refer to levels of control.
* In a centralized system, control is exerted by just one entity (a person or a leadership team, for example).
* In a decentralized system, there is no single controlling entity. Instead, control is shared among several independent teams or entities.
Location of Parts of System
Co-location and Distribution refer to differences of location.
* In a co-located system, parts of the system communicate within the same physical location (interaction between server and database, for example).
* In a distributed system, parts of the system are scattered and communicate all over the globe.