Dear Student,
A neodymium magnet is a permanent magnet made from an alloy of neodymium, iron and boron to form the Nd2Fe14B tetragonal crystalline structure. They are extremely resistant to demagnetization by external magnetic fields.
Ordinary magnet are made from strontium or barium ferrite. They are less expensive and more powerful. They have high temperature. Ordinary magnets are easy to magnetize. They are very resistant to corrosion and generally do not need extra coatings for corrosion protection.