Permanent magnets

Any ferromagnetic material, or substance whose atoms can be permanently aligned, can be made into a permanent magnet. These are the magnets you probably played with as a child. Some alloys can be made into stronger magnets than others.
One alloy that is especially suited to making strong magnets is alnico. This word derives from the metals that comprise it: aluminum, nickel and cobalt. Other elements are often added, including copper and titanium. But any piece of iron or steel can be magnetized, at least to some extent. You might have used a screwdriver, for example, that was magnetized, so that it could hold on to screws when installing or removing them from hard-to-reach places.
Permanent magnets are best made from materials with high retentivity. Magnets are made by using a high-retentivity ferromagnetic material as the core of an electromagnet for an extended period of time. This experiment is not a good one to do at home with a battery, because there is a risk of battery explosion.
If you want to magnetize a screwdriver a little bit so that it will hold onto screws, just stroke the shaft of the screwdriver with the end of a bar magnet several dozen times. But remember that once you have magnetized a tool, it is difficult to completely demagnetize it.