The basics

What?

The Le Mans 24 Hours is an invitational race run by the Automobile Club de l'Ouest (ACO - literally "Automobile Club of the West"). It has been running since 1923 when the winners completed more than 2200km - this year we can expect the winners to run for over 5200km.

Where?

The track is in the middle of France, just outside the town of Le Mans. It is about 8.5 miles long, mostly on narrow public roads with 200+mph straights interrupted by chicanes. There's a are more flowing sections at each end which are quite technical. The race attracts over 250,000 attendees from all over the world who almost all camp on-site, and they flood the track after the race.

When?

Qualifying is on Wednesday and Thursday evenings. The race starts on Saturday at 3pm French time, that's 2pm UK time (GMT+1) - but be sure to be around for a good hour beforehand for the build-up. And obviously, it runs to the same time the next day, as if you needed telling..

Who?

There are 56 cars split across four classes. The prestige of the overall win will be fought by the LMP1 cars, but other runners will tell you a class win is just as important to them. The classes:

• LMP1 is the main class. It is aimed at manufacturers (Audi, Peugeot) and top privateers. The frontrunners are diesel-powered and they have distinct advantages: they have more torque, and they have better fuel consumption. To try and offset this organisers have restricted their max.fuel to 51 litres, petrol cars can have 60 litres.. but since the petrol cars are not manufacturer entries they are still a way behind. Race lap time roughly 3m23s for diesels, 3m28 for the petrol cars.
• LMP2 is aimed at privateers only. These cars are smaller than the P1 cars and can be quite unreliable, often a case of 'last car standing'. These run to the slower LMS rules, unlike the ALMS where they can run alongside LMP1. Laps at roughly 3m38s.
• LMGT1 is the top production class with Corvettes and Aston Martins. New rules mean a new generation of car which is slower than before, but there aren't enough yet (only the Ford GT is here) so the older cars have been pegged back. Lap times were 3m54s, times from free practice suggest 3m58s now.
• LMGT2 is the slowest class and are more heavily restricted on aero and engines compared to GT1. This is the hunting ground of Porsche and Ferrari but this year there's a challenge from Corvette (formerly in GT1) and BMW to keep them honest. Lap time of about 4m02s. Often the most frenetic race, these guys are relentless.

Teams and drivers

There are fascinating stories up and down the grid, from the manufacturer powerhouses down to the smallest teams, from the first-timers (some new, some successful elsewhere) to veterans who count this race as their 20th. Right now winning is everything, yet by 6am Sunday some will be hoping just to make the finish - and will consider it a major acheivement if they do. There isn't the time to tell these stories now, we'll let them develop naturally over the week.

For now, let's have a look at the main contenders for the overall win.

The reigning champions of Le Mans:

Team Peugeot Total / Peugeot Sport Total

Car: Peugeot 908 HDi FAP

This is Peugeot's fourth year back in sportscars. Last year, it won for the first time since 1993 and for the two years before that had pushed Audi hard for the victory.

#1: Anthony Davidson, Alexander Wurz, Marc Gene

Alexander helped Peugeot to victory in 2009 and had previously driven in F1 for ten years, scoring several podiums in the process. Marc was also part of the Peugeot team's winning driver line-up last year. Before that, he was best known for being a F1 driver, doing two seasons for Minardi and two races as a stand-in at Williams. Anthony is new to Peugeot this year, replacing David Brabham. He is more commonly seen either behind a microphone in the 5 Live F1 booth or competing in ALMS.

#2: Franck Montagny, Nicolas Minassian, Stéphane Sarrazin

Sidepodcast favourite Franck was last seen in sportscars doing 70% of the driving at the Spa LMS race, which must be good preparation for the exhaustion of doing a 24-hour race. Apart from being Christine's favourite driver, he is also known for doing 7 F1 races for Super Aguri. Also seen in Superleague.

Nicolas missed the Spa LMS race due to injury - hopefully he will have recovered and be back to his usual level of performance, which was enough to help Peugeot to second place in 2008.

Stéphane rallies in the IRC as well as sportscar racing in the Le Mans Series. Came second in Spa last month.

#3: Sébastien Bourdais, Simon Pagenaud, Pedro Lamy

Sébastien grew up in the town of Le Mans and entered the 24hrs from 1999-2003 (not 2002) with a best finish of 4th for Pescarolo, before claiming 2nd with Peugeot in '07 and '09. He's previously done a year-and-a-half of F1, some Superleague... and won four CART championships. He was part of the team which won at Spa last month.

Back in the mid-90s, Pedro Lamy was a F1 backmarker. Since then he's won the Nurburgring 24 Hours twice and the Le Mans Series in two different classes (GT1 and LMP1). One of the three drivers who won at Spa last month.

Simon has done two Le Mans 24 Hours races but has never finished. He was more successful in the ALMS with Highcroft where he is a race winner alongside David Brabham, in ChampCar where he came 8th in 2007, and in the Le Mans Series where he won at Spa.

Team ORECA Matmut

Car: Peugeot 908 HDi FAP

#4: Nicolas Lapierre, Olivier Panis, Loic Duval

Last year, Team ORECA Matmut came joint 8th in the LMP1 class of LMS. In 2007, it bought out Courage in order to build its own prototypes. The dynamic duo of Panis and Lapierre move from the sister team and look very, very strong. Working alongside the factory cars, could be fast enough to ruin Audi's day.

It is also running it's own car, the #6 ORECA-AIM 01 with Ayari, Andre and Meyrick which may contend for the 'petrol' class, however the team is focussing most of its efforts on the 908.

Nicolas has been in the Le Mans 24-hour race twice and had a successful junior single-seater career. Most notably, he was the winner of the 2005-2006 A1GP series for France. Olivier's name will be familiar to F1 viewers of the late 1990s and early 2000s as the dignified, polite and loyal racer who won the chaotic 1996 Monaco Grand Prix. After leaving F1, he took a year out then came to ORECA and has been reasonably successful. Loic won last year's Formula Nippon championship and came 8th on his debut at the Le Mans 24 Hours in 2008.

And their main opposition:

Audi Sport Team Joest / Audi Sport North America

Car: Audi R15-plus TDI

Audi have been dominant at Le Mans and in this style of racing since the turn of the century with the R8, the R10 and the R15 with only a gap for sister marque Bentley in 2003. They'll be hoping the revised R15, the 'plus', will allow it to retake the crown lost to Peugeot last year.

#7 Allan McNish, Tom Kristensen, Rinaldo 'Dindo' Capello

"Dindo" is an extremely experienced and talented endurance driver on both sides of the Atlantic - he's won Petit Le Mans a record five times (2000, 2002 and 2006-2008), been ALMS champion twice (2006-2007) and won in the top tier at Le Mans 24h three times (2003, 2004 and 2008). Tom's record 8 Le Mans 24 victories (1997, 2000-2005 and 2008) and good record in ALMS mean that he will surely hit the ground running. His 3rd place in last month's Spa race should help convince people he still has what it takes to succeed at this level. Allan did a season of F1 at Toyota, but his primary achievement in motorsport has been his role in Audi's sportscar success. He has won Le Mans 24h twice (1998 and 2008) and won ALMS three times (2000, 2006 and 2007). At the Spa LMS round Audi used as a "warm-up event", Allan was part of the team that came 3rd.

#8 Marcel Fassler, Andre Lotterer, Benoit Treluyer

The junior line-up in this year's squad, they've been around sportscars and other forms of racing for a little while and this is their first (second for Fassler, who was with Audi last year) shot with a big manufacturer in this race. Some may view dropping the likes of Lucas Luhr a mistake. All are fast but unproven over this distance at this level. Lotterer did finish 7th with the customer Kolles Audi team last year.

#9 Romain Dumas, Timo Bernhard, Mike Rockenfeller

Dumas and Bernhard have been paired together for many years across a wide variety of cars from Porsches in GT2, via Porsches in LMP2, and are now with sister-brand Audi. Both are considered near-faultless but they do have to learn the car. Rockenfeller usually races in DTM, he's fairly quick but a little erratic.

The rest

Those are the cars in the fight for the race win, as for the others we'll just summarise each class - if you have any questions about the other teams, cars or drivers please do just ask either here or in the live commenting threads, there are bound to be people around who can help.

LMP1 petrol: There is no official petrol class at Le Mans, but such is the performance differential between them and Audi/Peugeot they are effectively not racing each other. This fight is between the Rebellion Lola-Judds and the Aston Martin Lolas, each run two cars with solid professional driver line-ups. Perhaps AMR has the slightly better car. The ORECA-AIM is a potent weapon and will be fast over a lap, but perhaps not over several stints with this driver line-up. The Kolles Audi R10s have a weaker line-up and the team has been distracted with the boss running off with Hispania and have done little testing, so these diesels shouldn't be a factor.

LMP2: Everyone is looking at the Highcroft team who are currently winning races in the ALMS, and making their first appearance at Le Mans. Strakka has a very similar car but is a customer, Highcroft developed it along with Wirth Research - yet Strakka has vital 24hr experience from previous years with other cars, that Highcroft lacks. The fight should be between these two, with the RML Lola-HPD not far back. The rest won't run them close unless it turns into a reliability run - which is very much possible in this class.

GT1: Young Driver AMR's sole DBR9, with the relentless Tomas Enge on board, will make the fight a tough one and they are favourites, though surely with the works 'Vettes moving to GT2 it opens the door for the Luc Alphand versions.. It will be interesting to see the new-gen GT1 Fords in a proper endurance race for the first time - have they got it or not?

GT2: Anybody's guess! Corvette have been bulletproof in GT1 for years and they've taken their speed to GT2. They've got to contend with some exceptional Porsche and Ferrari entries from the likes of Felbrmayr and Risi, respectively (among many more), as well as that Schnitzer BMW attack - Schnitzer are a very good team but their car may not be a match yet, it is early in its development cycle. And don't forget the Spykers! Everyone loves the Spykers. One thing about GT2: don't think because it is the 'small' class the drivers are any worse than in the other classes, they very much aren't - this class contains some very high quality drivers.

More information

This race may not be for everyone. If you like strategy and watching events play out over a few hours, this race is for you. The choice whether or not to double-stint or even triple-stint the drivers and/or the tyres, and whether to fuel light or not, can be fascinating - Audi are particularly good at this and in the past have used it well to fight Peugeot's speed advantage. Tortoise or hare? The choices teams have made echo all through the grid.

Just when things settle down is when the track will bite - some cars will need a long stop for repairs and begin to fight back. Some drivers will get tired and make errors. Stock up the energy drink and the coffee and settle in to Radio Le Mans, they'll explain everything.

Please refer to the live commenting threads as they are posted to Sidepodcast over the week, these will contain all the resources you need.