What is the difference between petrol and diesel car?

In simple words, petrol - low compression spark ignited

Diesel - High compression Compression ignited

The basic difference between diesel and gaslione is how  these explosions happen?

diseal by self ignition/ compression ignition CI

( instantaneous injection* at high pressure in pressure stroke).

gaslione by sprk plug ignition/ sprk ignition

(  before top dead centre (BTDC)** the sprk give the ignation

take care : most modern car and maybe all now used injectors to inject the fuel in cylinder that means we have also injectors in gasoline engine but the difference we need a spark plug in gasoline engine to burn the fuel .while we dont need this spark in diesel because the fuel(diesel ) burn by self ignition @ high pressure.

If we can burn gasoline by self ignition.

(its  a revolution in the world of engines and related worlds)

*this is a one from the most important things that has to be taken into consideration in the process of engine design.

**the endpoint when the piston moves to up

Gasoline and Diesel

*Spark ignition and compression ignition.

*Air Fuel Ratio is not as important in Diesel as Gasoline

*Way high Fuel pressure in a Diesel Engine

*Emissions are different in diesel.

*Engine parts are heavier in diesel

*Diesel engine has higher mechanical efficiency.

*higher torque in diesel engine

etc etc

in petrol engine start with help of spark engine and in diesel engine the air is compress