What's the difference between magnet wire and resistance wire? Which is better for building an electromagnet?
Resistance wire will be made of some higher-resistance material than copper and may or may not be insulated, so will have a higher resistance than the same size and length of copper wire. Resistance wire would normally be used to make a heating element.
Magnet wire is copper, with a thin "enamel" insulation, and is intended for winding coils for an electromagnet.