These are the lecture notes for a course on Khovanov homology held at Gökova Geometry Topology Institute in Summer 2022. In these notes, we introduce Khovanov homology, the Lee spectral sequence, Lee homology and Rasmussen's \(s\)-invariant after providing sufficient background in knot theory and spectral sequences. We tried to provide a self-contained and short overview of the topics. Most of the lectures are geared towards graduate students with basic knowledge in low-dimensional topology and algebraic topology. We end the notes with applications in low-dimensional topology.