Magnetism is very important part to physics. It is a very fundamental properties of materials. It is also very important in daily life. Magnetic properties of lots of material is used to build lots of machine and tools. For example we produce electricity using the electromagnetic induction. Motors also works with electromagnetic induction. Even hard disc of our computer stores data using the magnetic properties of the materials. Compass also works using magnetic properties. Even to understand the behaviour of light in any medium we have to understand magnetism also because light is a electromagnetic wave.
There are immense number of usage of magnetism, that's why it is important to know magnetism.
