As the first grand slam event of the year, the Australian Open is unique. It is played in the highest temperatures of any of the four major tennis tournaments and is the only one played in the Southern Hemisphere.
Only the U.S. Open has hard courts similar to those in Melbourne. And daytime matches often are staged with temperatures near or over 100 degrees.
The start of the 2015 tennis season ends the long pause after the U.S. Open and is followed by another pause before the French Open.
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Here's a look at this year's Australian Open.
WHEN: Technically, the event is already under way. Qualifying matches flesh out the field ahead of the tournament proper. First official matches are Jan. 19, and the men's final concludes on Feb. 1. This is the 103rd Aussie.
WHERE: Melbourne Park is in Australia's second-largest city. It is in the state of Victoria. Melbourne Sports and Entertainment Precinct is the hub of sports activities that includes baseball. The venue was built in 1988 to replace outdated and undersized Kooyong Lawn tennis Club. It was known as Flinders Park until 1996.
The main court is Rod Laver Arena, honoring the tennis great. It holds 15,000 and has a retractable roof.
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FACTS: Since its first run in 1905, the tournament has been played in five Australian cities and two in New Zealand. … Foreign players began to arrive in numbers in 1946, by boat. … Laver won three times. He was the first winner in the open era of professional tennis … More than 643,000 people attended Open matches in 2014. The largest attendance was 686,006 in 2012. … Winners get more than $2 million.
WEATHER: Moderate and dry to start, with highs in the upper 70s to mid-80s. It's mid-summer Down Under, so expect triple digits at some point but little chance of rain.
TV: In the U.S., matches are carried by ESPN and The Tennis Channel.
DEFENDING CHAMPIONS: Stan Wawrinka of Switzerland returns. Li Na of China retired after last season.
FORMER MEN'S CHAMPIONS IN THE FIELD: Novak Djokovic, 2008, 2011, 2012, 2013; Roger Federer, 2004, 2006, 2007, 2010; Rafael Nadal, 2009.
FORMER WOMEN'S CHAMPIONS IN THE FIELD: Serena Williams, 2003, 2005, 2007, 2009, 2010; Victoria Azarenka, 2012, 2013; Maria Sharapova, 2008.
AMERICAN MEN'S WINNERS: Arthur Ashe, Roscoe Tanner, Vitas Gerulaitis, Brian Teacher, Jim Courier, Pete Sampras, Andre Agassi. Agassi won three times and is the most recent U.S. winner, in 2003.
AMERICAN WOMEN'S WINNERS: Barbara Jordan, Chris Evert (twice), Martina Navratilova (twice), Monica Seles, Lindsey Davenport, Jennifer Capriati, Serene Williams. Williams won five times, most recently 2010.
FAVORITES: Djokovic is even money to win, with Nadal and Federer at 6-1. Williams is even money, followed by Azarenka, Sharapova and Simona Halep at 7-1.