This lecture covers the concept of linear maps, focusing on the basis of the space of linear maps. It discusses the freedom of the family of applications and the composition of linear applications. The lecture also delves into the coordinates of vectors in different bases and the associated matrices. Theorem 7.4 is presented, highlighting the coordinates of vectors in a given base. Proposition 7.7 is explored, demonstrating the relationship between linear maps and their coordinates. The lecture concludes with the composition of linear applications and the coefficients in different bases.