  The notion of $\tau$-tilting theory was introduced by Adachi, Iyama and
Reiten at the beginning of the last decade and quickly became one of the most
active areas of research in the representation theory of finite dimensional
algebras. The aim of these notes is two-fold. On the one hand, we want to give
a friendly introduction to $\tau$-tilting theory to anyone with a small
background in representation theory. On the other, we want to fill the apparent
gap for a survey on the subject by collecting in one place many of the most
important results in $\tau$-tilting theory.
