Magnetism

Magnetism is an invisible force or field caused by the unique properties of certain materials. In most objects, electrons spin in different, random directions. This causes them to cancel each other out over time. However, magnets are different. 

In magnets the molecules are uniquely arranged so that their electrons spin in the same direction. This arrangement of atoms creates two poles in a magnet, a North-seeking pole and a South-seeking pole.

The Earth is a giant magnet At the center of the Earth spins the Earth's core. The core is made up of mostly iron. The outer portion of the core is liquid iron that spins and makes the earth into a giant magnet. This is where we get the names for the north and south poles. These poles are actually the positive and negative poles of the Earth's giant magnet. 

This is very useful to us here on Earth as it lets us use magnets in compasses to find our way and make sure we are heading in the right direction. It's also useful to animals such as birds and whales who use the Earth's magnetic field to find the right direction when migrating. Perhaps the most important feature of the Earth's magnetic field is that it protects us from the Sun's solar wind and radiation.

Magnets can be used for:

Temporarily mounting objects to other ferromagnetic material

Creating a compass

Building speakers and microphones

Recording data, video, or audio on tapes or other magnetic data storage systems like hard drives

Toys

Pickups on electric guitars

Magnetic strips on credit, debit, and other banking cards

Electric motors

Moving large pieces of scrap metal, such as cars

Mag-lev (or “magnetic levitation”) trains 

Generating electricity

Magnetic Resonance Imaging (MRI’s)