Why A resistor's whole job is to oppose current flow, and that opposition is measured in ohms. Ohm's law, I = E/R, shows that for a fixed voltage, more resistance means less current. In a DC circuit the resistor is the component that sets or limits current and drops voltage.
Watch out An inductor opposes a change in current, but once DC settles to a steady value the inductor looks like a plain piece of wire with almost no opposition. A transformer only works with changing (AC) current, and an inverter converts DC to AC.
Resistor = resists. Ohms oppose current in DC; inductors only fight changes, not steady DC.