Why Don't Cars Need a Choke?

Edit: From the answers I've received, I suppose what I'm wondering is, how does the automatic choke work? Especially in older cars that didn't have computers.
An automatic choke uses a metal spring to open and close the choke plate [2]. In modern cars, the fuel injection controls the amount of petrol in the petrol/air mix, so they do not need a choke [1].
Cars don't need chokes because most modern cars have fuel injection and computerized monitoring and adjustment of the petrol-air mix [1]. The fuel/air mixture has more fuel and less air, and possibly a bit extra fuel as well [1]. The automatic choke has rods linking the choke to the throttle, and it operates a fast-idle cam that keeps the throttle from closing tight [2]. The idle speeds up as the engine warms up, and the choke opens wider as well, allowing more air into the mix [2].