A number of important equations relating various parameters relevant to MRI physics.
A few diagrams depicting various pulse sequences.
Diagrams depicting the effect of material (grey) on magnetic field (blue lines), depending on the materials properties: ferromagnetism, diamagnetism, paramagnetism, and superparamagnetism.
Flow-related enhancement is an enhancement of flowing blood seen on gradient echo pulse sequences as well as in entry slices of multslice spin echo sequences.
RF coils are the "antenna" of the MRI system that broadcasts the RF signal to the patient and/or receives the return signal. RF coils can be receive-only, in which case the body coil is used as a transmitter; or transmit and receive (transceiver).
Case Discussion
Some of these diagrams are based on those of Ray Ballinger of MRItutor.org who kindly donated their content to Radiopaedia.org in 2013.