What is a resistor?

Answer 1

A resistor is a device that resists, or limits, the flow of electric current through itself. The more resistance a thing has, the more it limits current (at the same voltage). In a circuit, resistance and current are inversely proportional. The more the resistance, the more current will be limited and the less current will actually flow. Resistors pay a price for limiting current - they create heat.

In other words, resistors convert electrical energy into heat energy.

It might be convenient to divide resistors into just two groups for this discussion (though there are many possible ways to catagorize them). Resistors might be though of as electronic components, or as thermal elements in a device or equipment. A resistor "sorta" conducts current flow, but it heats up as a consequence to having current "forced" through it by some applied voltage. If the resistor is an appliance, it is probably being used specifically to generate the heat, because the heat is what is desired. We need to dry our hair, or the clothes. We want to make toast or coffee or bacon. Incandescent lights could be seen as resistors, but we don't (usually) use them to generate heat. Heating elements, or thermal elements, are heaters - resistive heaters. In electronics equipments, resistors are included in circuit designs to "develop" voltage and to limit current. They are an integral part of the electronics world, and anyone entering in will be seeing them and solving a number of problems with resistance, current and voltage within a short time of arriving.