The bar magnet is introduced as a fundamental aspect of magnetism, illustrating magnetic pole behavior. By sprinkling iron filings on a glass sheet above a bar magnet, students visualize the magnetic field lines that emerge from both poles of the magnet. This practical demonstration emphasizes that each magnet has a North pole and a South pole, which aligns itself with the Earth's magnetic field when freely suspended. The mention of a current-carrying solenoid indicates a broader context of electromagnetism, linking static and dynamic magnetic fields.