Phenomenon exhibited by materials like iron (nickel or cobalt) that become magnetized in a magnetic field and retain this magnetism when the field is removed. Ferromagnetism is one of the strongest forms of magnetism. It is responsible for most of the magnetic behavior encountered in everyday life and, along with Phenomenon in iron or iron alloys with a body centered cubic crystal structure where there can be incomplete cancellation of antiferromagnetic arranged spins giving a net magnetic moment. This happens when the sublattices consist of different materials or ions (such as Fe, is the basis for all permanent magnets (as well as the metals that are noticeably attracted to them).
Some or all content above used with permission from J. H. Wittke.