A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for properties of a magnet: a force that pushes/repels or pulls/attracts on other magnetic materials like iron and/or other magnets.
A permanent magnet is an object made from a material that is magnetized and creates its own magnetic field. An everyday example is a refrigerator magnet used to hold notes on a refrigerator door. Materials that can be magnetized, which are also the ones that are strongly attracted to a magnet, are described as magnetic, ferrous, ferromagnetic and ferrimagnetic. These include iron, nickel, cobalt, some rare earth metals and some of their alloys and some naturally occurring minerals such as lodestone.
Some ferromagnetic materials can be magnetized by a magnetic field but do not tend to remain magnetized when the field is removed, they are described as soft. Permanent magnets are made from ferromagnetic materials that stay magnetized and are described as hard.
An electromagnet is made from a coil of wire which acts as a magnet when an electric current passes through it, but stops being a magnet when the current stops. Often an electromagnet is wrapped around a core of ferromagnetic material like steel, which enhances the magnetic field produced by the coil.
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