An Introduction to Schur Polynomials

Notes from a course at the ATM Workshop on Schubert Varieties, held at The Institute of Mathematical Sciences, Chennai, in November 2017. Various expansions of Schur functions, the Lindstr"om-Gessel-Viennot lemma, semistandard Young tableaux, Schensted’s insertion algorithm, the plactic monoid, the RSK correspondence, and the Littlewood-Richardson rule are discussed.