There are five types of modern permanent magnets, each made from different materials with different characteristics.
The strongest magnets, referred to as rare earth magnets, are commonly known as neodymium magnets which are made from an alloy of neodymium, iron and boron (NdFeb) and samarium cobalt magnets which are made from samarium, cobalt and small amounts of iron, copper and other materials.
Other types of permanent magnets include ferrite magnets, made from a compound of ceramic material and iron oxide (SrO.6Fe2O3), alnico magnets made from aluminium, nickel and cobalt and flexible rubber.