Spherical magnets, like all other magnets, have a south pole and a north pole on opposite sides of the magnet. Spherical magnets come in a range of sizes. The largest currently available has a diameter of 30mm and a strength of 13kg.
Unlike most other magnets, sphere magnets have a chromium coating instead of nickel. Chromium is necessary because the spherical shape means that a large amount of pressure can be applied to a small area of the surface when attached to, for example, a metal plate. Chrome is more durable than nickel in these situations and therefore provides better protection. Despite the chrome coating, you still need to be careful. Heavy blows and collisions with other magnets WILL damage the sphere magnet despite the chrome coating.
Sphere magnets are usually bought for both play and practical purposes. Combine sphere magnets with rod magnets and you can spend hours building all sorts of creative structures. Please note that sphere magnets are not intended for use by small children. Swallowing the magnets can cause serious damage to internal organs. On a more practical note, sphere magnets can be used as connectors between toy train cars, for example.