This lesson builds upon the previous lessons on vectors and coordinates, introducing more advanced concepts such as imaginary and complex numbers, as well as extending the discussion to three-dimensional space. We will explore how to represent vectors in 3D using the i, j, and k unit vectors, and how to perform operations such as addition, subtraction, and dot products in this context. Additionally, we will discuss the process of normalisation, which is essential for working with unit vectors. By the end of this lesson, you will have a deeper understanding of how to manipulate vectors in both 2D and 3D spaces.