A ferromagnetic material is one that has magnetic properties similar to those of iron. In other words, you can make a magnet out of it.
Magnetic fields come from currents.
Each electron has a spin. This is a quantum mechanical phenomenon that is difficult to make a comparison to, but can be thought of as similar to the rotation of the Earth about its axis. Electron spins are in one of two states, up or down. Electrons are arranged in shells and orbitals in an atom. Secondly, domains which are aligned with the field will expand to take over regions occupied by domains aligned opposite to the field.