Fundamental interaction and the strong interaction. Their magnitude and behaviour vary greatly, as described in the table below. Modern physics attempts to explain every observed physical phenomenon by these fundamental interactions. Moreover, reducing the number of different interaction types is seen as desirable. Two cases in point are the unification of: Both magnitude ("relative strength") and "range", as given in the table, are meaningful only within a rather complex theoretical framework. It should also be noted that the table below lists properties of a conceptual scheme that is still the subject of ongoing research. The modern (perturbative) quantum mechanical view of the
Interaction technique line and direct manipulation user interfaces. While interaction techniques are typically technology-, platform-, and/or implementation-dependent (see #level of granularity above), human-computer or human-information interactions can be characterized at higher levels of abstraction that are independent of particular technologies and platforms. At such levels of abstraction, the concern is not precisely how an interaction is performed; rather, the concern is a conceptual characterization of what the interaction is, and what the general utility of the interaction is for the user(s). Thus, any single interaction pattern may be instantiated by any number of interaction techniques, on any number of different technologies and