The Indianapolis 500 is a major sporting event, and as such it has it's own intricate set of rules. Most of them don't matter unless something strange or unlikely comes up, but there are a few Indy 500 rules that fans should be familiar with. Here. then, is your quick Indy 500 rules primer:

Qualification

Qualifying rules were changed in 2005 to make them more interesting for fans to watch. In other words, they figured out that more people would come watch qualifying if it were fun to watch, and more people means more ticket sales. There are four days of qualifying. Each car is allowed three qualifying attempts per day. There are 33 total spots available in the race, and 11 are available each day. Drivers can make another attempt to qualify if they have made one if they choose to withdraw their time. Any spots that are not filled on one day are carried over to the next day. On the fourth day, the slowest driver from the first three days is on the bubble and can be replaced if a non-qualified driver puts up a better time. The track is open from noon to 6 p.m. each qualifying day. Drivers draw a number each day to determine the order of their qualification attempt. Each driver is guaranteed a qualifying attempt even if weather cuts the qualifying period short. In that case they would be able to try to qualify the next day and have it qualify for the original day.

Number of cars

Any car that is entered in the race is allowed to have two different vehicles under the same number. The second car is denoted by a T beside the number - the second car for the 23 entry, for example, would be 23T. Both cars can be used for practice throughout the month. If a backup car is running particularly well during the practice period it can be entered separately as its own car with it's own driver. The backup cars from the better teams are often sold to other teams to be used in the race as well.

Technical rules

The specification for cars in the Indy 500 are now the same as they are for the Indy Racing League, and the League administers the rule. The only difference between Indy 500 cars and cars for the rest of the circuit is that a special wing is used that provides lower drag. This consistency is perfectly logical, but it hasn't always been the case. For many years the USAC sanctioned the race and set the rules, and CART sanctioned the rest of the circuit. That created several circumstances where the cars had to be much different for the Indy 500 than for the rest of the races. There were several different engines and chassis developed for and raced at the Indy 500 that couldn't be used anywhere else.

Inspections

Cars have to pass several inspections before they start the race. The first occurs before the car is allowed to practice and is designed to make sure that the car is safe. The second inspection is required before a car can attempt to qualify. At that time the car is checked very closely to make sure that it meets all technical specifications and will qualify legally if it is able to go fast enough.

Sexism?

Janet Guthrie became the first woman to qualify for the Indy 500 in 1977. What's remarkable about that is it was just six year after the archaic rule that banned women from driving and from being in the pits or garage was abolished. In 2008, two women - Danica Patrick and Sarah Fisher - will be attempting to qualify. When women are in the field the traditional call of 'Gentlemen, start your engines' is changes to 'Ladies and Gentlemen, start your engines'.