Major Tennis Competitions

Roger Federer of Switzerland
While the entry level of professional tennis play is the ITF Futures circuit, with tournaments at two prize money levels, the university of modern Tennis are the ATP circuits and at the peak, the Grand Slam tournaments.
 Grand Slam tournaments
The four Grand Slam tournaments are the most prestigious tennis tournaments in the world. They are held annually and include, in chronological order, the Australian Open, the French Open, Wimbledon, and the US Open. Apart from the Olympic Games, Davis Cup, Federation Cup, and Hopman Cup, they are the only tournaments regulated by the International Tennis Federation (ITF).
Aside from the historical significance of these events, they also carry larger prize funds than any other tour event and are worth double the number of ranking points to the champion than in the next echelon of tournaments, the Masters 1000 (men) and Premier events (women). Another distinguishing feature is the number of players in the singles draw, 128, more than any other professional tennis tournament. This draw is composed of 32 seeded players, other players ranked in the world's top 100, qualifiers, and players who receive invitations through wild cards. Grand Slam men's tournaments have best-of-five set matches throughout.
 

 Grand Slam
Period
Tournament
Location
Surface
January
Australian Open
Melbourne
Hard (Plexicushion)
May-June
French Open
Paris
Clay
June-July
Wimbledon
London
Grass
August-September
US Open
New York City
Hard (DecoTurf) 

Masters 1000
 
The ATP World Tour Masters 1000 (previously known as the Masters Series) is a group of nine tournaments that form the second-highest echelon in men's tennis. Each event is held annually, and a win at one of these events is currently worth 1000 ranking points. In November, at the end of the tennis year, the world's top eight players compete in the ATP World Tour Finals, a tournament with a rotating locale.

Current Masters 1000 tournaments (2012)
Start Month
Tournament Name
City
Surface
Opening
March
BNP Paribas Open
Indian Wells
Hard
Outdoors
March
Sony Ericsson Open
Miami
Hard
Outdoors
April
Monte-Carlo Rolex Masters
Monte-Carlo
Clay
Outdoors
April
Internazionali BNL d'Italia
Rome
Clay
Outdoors
May
Mutua Madrileña Masters Madrid
Madrid
Clay
Outdoors
August
Rogers Cup
Toronto
Hard
Outdoors
August
Western & Southern Financial Group Masters & Women's Open
Cincinnati
Hard
Outdoors
October
Shanghai Masters 1000 presented by Rolex
Shanghai
Hard
Outdoors
November
BNP Paribas Masters
Paris
Hard
Indoors

250 and 500 Series
 
The 500 Series consists of 11 tournaments and the 250 Series runs to 40 tournaments. Though less than the Masters 1000, these events offer large amounts of prize money. The Barclays Dubai Tennis Championships offer the largest 500 Series prize to players, with total prize money of US$1,426,000.
 
Premier events for Ladies
 
Premier events for women form the most prestigious level of events on the Women's Tennis Association Tour after the Grand Slam tournaments. These events offer the largest rewards in terms of points and prize money. Within the Premier category are Premier Mandatory, Premier 5, and Premier tournaments. The tiering system in women's tennis was introduced in 1988. At the time of its creation, only two tournaments, the Lipton International Players Championships in Florida and the German Open in Berlin, comprised the Tier I category. In 2009, four tournaments are Premier Mandatory, five tournaments are Premier 5, and ten tournaments are Premier.