Here's the breakdown:

* Petrol (or gasoline) is a refined petroleum product. It's a highly flammable liquid used as fuel for internal combustion engines in cars, motorcycles, and many other vehicles.

* Oil is a naturally occurring, viscous liquid found beneath the Earth's surface. It's a complex mixture of hydrocarbons.

Think of it this way:

* Oil is like the raw ingredient, a complex mixture of hydrocarbons.

* Petrol is like a processed food, specifically refined for use as fuel.

Petrol is extracted from crude oil through a process called refining. This process separates the different components of crude oil and creates various products, including petrol, diesel, kerosene, and others.