* Contact forces require direct physical contact between objects. Examples include friction, normal force, and applied force.
* Non-contact forces can act on objects without any physical touch. Gravity and magnetism fall into this category.
Gravity acts between any two objects with mass, regardless of whether they are touching. It's the force that keeps us on the ground and the planets in orbit around the sun.
Magnetism is a force that arises from the movement of electric charges. Magnets exert forces on other magnets and on ferromagnetic materials like iron, even when they are not in direct contact.
Let me know if you'd like more detail on either gravity or magnetism!
