Hi,
This is a fundamental question and I am glad you asked. A year is defined as approximately the length of time it takes to go around the Sun. So next March 20th, (2009) we will have gone around the Sun about 1 time. If you watch the stars at night, you will see that the same constellations show up at the same time of year. This is related to the fact that the Earth takes about a year to orbit the Sun. We cut that year up into months and days, but because 24 hours in a day and 12 months a year doesn't quite exactly equal the time we go around the Sun, we have to add a day (leap day in February) every 4 years. So the real answer to your question is it takes about a year + 6 hours + some minutes + some seconds.
Laura