How many formula 1 championships has Fernando alonso won?

On September 25, 2005 Fernando Alonso won the Formula One World Driver's Championship title at the age of 24 years and 58 days, thus breaking Emerson Fittipaldi's record of being the youngest Formula One World Drivers' Champion (this record was subsequently broken by Lewis Hamilton). After retaining the title the following year, Alonso also became the youngest double Champion. In 2007, he became the second F1 driver, after Michael Schumacher, to score at least 100 points for three consecutive seasons.