Published online by Cambridge University Press: 06 October 2015
In this paper we give a formula for the $K$ -theory of the
$C^{\ast }$ -algebra of a weakly left-resolving labelled space. This is done by realizing the
$C^{\ast }$ -algebra of a weakly left-resolving labelled space as the Cuntz–Pimsner algebra of a
$C^{\ast }$ -correspondence. As a corollary, we obtain a gauge-invariant uniqueness theorem for the
$C^{\ast }$ -algebra of any weakly left-resolving labelled space. In order to achieve this, we must modify the definition of the
$C^{\ast }$ -algebra of a weakly left-resolving labelled space. We also establish strong connections between the various classes of
$C^{\ast }$ -algebras that are associated with shift spaces and labelled graph algebras. Hence, by computing the
$K$ -theory of a labelled graph algebra, we are providing a common framework for computing the
$K$ -theory of graph algebras, ultragraph algebras, Exel–Laca algebras, Matsumoto algebras and the
$C^{\ast }$ -algebras of Carlsen. We provide an inductive limit approach for computing the
$K$ -groups of an important class of labelled graph algebras, and give examples.