  By using C*-correspondences and Cuntz-Pimsner algebras, we associate to every
subshift (also called a shift space) $X$ a C*-algebra $O_X$, which is a
generalization of the Cuntz-Krieger algebras. We show that $O_X$ is the
universal C*-algebra generated by partial isometries satisfying relations given
by $X$. We also show that $O_X$ is a one-sided conjugacy invariant of $X$.
