what are dominds? does these dominds help magnets attract and repul?

A magnetic domain is region in which the magnetic fields of atoms are grouped together and aligned. You can think of magnetic domains as miniature magnets within a material. In an unmagnetized object,  all the magnetic domains are pointing in different directions. But, when the metal became magnetized, which is what happens when it is rubbed with a strong magnet, all like magnetic poles lined up and pointed in the same direction. The metal became a magnet. It would quickly become unmagnetized when its magnetic domains returned to a random order. 

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