The Specification Language TLA+
Résumé
The specification language TLA+ was designed by Lamport for formally describing and reasoning about distributed algorithms. It is based on a variant of Zermelo-Fränkel set theory and the Temporal Logic of Actions (TLA). A full description of the language and its use for specification appears in Lamport's book "Specifying Systems". This chapter aims at a formal definition of the core concepts of TLA and TLA+, motivating some choices, in particular with respect to competing formalisms.