Low emittance machines require lattices with many magnets of short length. Furthermore, successful lattices require strong gradients with strong dipole fields. These lattices are popular today, as MAX IV has demonstrated that a diffraction limited synchrotron light source can be based on such a lattice. This paper gives an overview of the various magnets used by the various diffraction limited light sources -available, under construction or designed. It compares the different magnet design and technology used and presents the magnet parameters in a consistent fashion.