Ferromagnetic, refers to the magnetic state of a material, with spontaneous magnetization. The most widely known in all materials to iron, hence the name.
Some materials are magnetized by the action of an external magnetic field, and even if the external magnetic field disappears, they can maintain their magnetized state and have a magnetic property, that is, so-called spontaneous magnetization. All permanent magnets are ferromagnetic or ferrimagnetic.
The concept of substantially ferromagnetic includes any substance that exhibits magnetism in the absence of an external magnetic field. So far still some people use this concept. However, scholars have defined the concept more precisely by having a deeper understanding of different magnetic materials and their magnetism. When all the magnetic ions in a material cell refer to its magnetic orientation, it is called ferromagnetic. If only part of the ion magnetic field pointing to the magnetic direction, then called ferrimagnetic. If the direction of their magnetic ions just offset each other (although all the magnetic ions only point to exactly the opposite two directions) is called antiferromagnetic.
The magnetic phenomena of matter have a critical temperature at which temperature does not occur. For ferromagnetic and ferrimagnetic materials, this temperature is called the Curie temperature; for antiferromagnetic materials, this temperature is called the Neel temperature.
Some people think that the attraction between the magnets and the ferromagnetic material is the earliest human understanding of magnetism.