What is the primary operational difference between a turbocharger and a supercharger?

1. A turbocharger is driven by engine exhaust gases, while a supercharger is driven mechanically by a belt from the engine crankshaft
2. A turbocharger pumps engine oil, while a supercharger pumps engine coolant
3. A turbocharger is used only on diesel engines, while a supercharger is used only on petrol engines
4. A turbocharger operates only at idle speeds, while a supercharger operates only at high speeds