This book is an introduction to basic concepts in ergodic theory such as
recurrence, ergodicity, the ergodic theorem, mixing, and weak mixing. It
does not assume knowledge of measure theory; all the results needed from
measure theory are presented from scratch. In particular, the book
includes a detailed construction of the Lebesgue measure on the real
line and an introduction to measure spaces up to the Caratheodory
extension theorem. It also develops the Lebesgue theory of integration,
including the dominated convergence theorem and an introduction to the
Lebesgue $Lp$spaces.