Editing Computation tree logic (section)

===Temporal operators===
The temporal operators are the following:
* Quantifiers over paths
**'''A''' &Phi;&nbsp;&ndash; '''A'''ll: &Phi; has to hold on all paths starting from the current state.
**'''E''' &Phi;&nbsp;&ndash; '''E'''xists: there exists at least one path starting from the current state where &Phi; holds.
* Path-specific quantifiers
**'''X''' ''φ''&nbsp;&ndash; Ne'''x'''t: ''φ'' has to hold at the next state (this operator is sometimes noted '''N''' instead of '''X''').
**'''G''' ''φ''&nbsp;&ndash; '''G'''lobally: ''φ'' has to hold on the entire subsequent path.
**'''F''' ''φ''&nbsp;&ndash; '''F'''inally: ''φ'' eventually has to hold (somewhere on the subsequent path).
**''φ'' '''U''' ''ψ''&nbsp;&ndash; '''U'''ntil: ''φ'' has to hold ''at least'' until at some position ''ψ'' holds. This implies that ''ψ'' will be verified in the future.
**''φ'' '''W''' ''ψ''&nbsp;&ndash; '''W'''eak until: ''φ'' has to hold until ''ψ'' holds. The difference with '''U''' is that there is no guarantee that ''ψ'' will ever be verified. The '''W''' operator is sometimes called "unless".

In [[CTL*]], the temporal operators can be freely mixed. In CTL, operators must always be grouped in pairs: one path operator followed by a state operator. See the examples below. [[CTL*]] is strictly more expressive than CTL.