  Discovering a new field is not usually an easy process, especially when you
choose magnetic resonance imaging (MRI). MRI is one of the few non-invasive
medical procedures, if not the only one, that someone can receive in modern day
hospitals. Its high sensitivity is a true prowess that is due to three things:
subtle quantum physics, great engineering and clever imaging techniques from
mathematics and computing science. However, the mathematics and physics of it
are already daunting tasks by themselves, which makes MRI difficult to
comprehend. This document paves a rather short, yet solid and logical, path
from the subtle concept of spin to the current limitations of diffusion MRI. It
then describes more advanced encoding methods designed to overcome diffusion
MRI's limitations, such as tensor-valued encoding.
