The types of coupling, in order of lowest to highest coupling, are as follows:
* '';Data coupling'' -: Data coupling is when modules share data through, for example, parameters. Each datum is an elementary piece, and these are the only data which are shared (e.g. passing an integer to a function which computes a square root).
* '';Stamp coupling (Data-structured coupling)'' -: Stamp coupling is when modules share a composite data structure, each module not knowing which part of the data structure will be used by the other (e.g. passing a student record to a function which calculates the student's GPA).
* '';Control coupling'' -: Control coupling is one module controlling the logic of another, by passing it information on what to do (e.g. passing a what-to-do flag).
* '';External coupling'' -: External coupling occurs when two modules share an externally imposed data format, communication protocol, or device interface.
* '';Common coupling'' -: Common coupling is when two modules share the same global data (e.g. a global variable).
* '';Content coupling'' -: Content coupling is when one module modifies or relies on the internal workings of another module (e.g. accessing local data of another module).
* In [[object-oriented programming]], ''subclass coupling'' describes a special type of coupling between a parent [[class (computer science)|class]] and its child. The parent has no connection to the child class, so the connection is one way (i.e. the parent is a sensible class on its own). The coupling is hard to classify as low or high; it can depend on the situation.
