when are the summer olympics held?
Once every two years
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 The Games have grown so much that nearly every nation is now represented . This growth has created numerous challenges and controversies , including boycotts , doping , bribery , and a terrorist attack in 1972 . Every two years the Olympics and its media exposure provide unknown athletes with the chance to attain national and sometimes international fame . The Games also constitute an opportunity for the host city and country to showcase themselves to the world . 

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 The modern Olympic Games or Olympics ( French : Jeux olympiques ) are the leading international sporting event featuring summer and winter sports competitions in which thousands of athletes from around the world participate in a variety of competitions . The Olympic Games are considered to be the world 's foremost sports competition with more than 200 nations participating . The Olympic Games are held every four years , with the Summer and Winter Games alternating by occurring every four years but two years apart . 

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 By 2016 , the Olympic Games will have been hosted by 44 cities in 23 countries , but by cities outside Europe and North America on only eight occasions . Since the 1988 Summer Olympics in Seoul , South Korea , the Olympics have been held in Asia or Oceania four times , a sharp increase compared to the previous 92 years of modern Olympic history . The 2016 Games in Rio de Janeiro will be the first Olympics for a South American country . No bids from countries in Africa have succeeded . 

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 The 114th IOC Session , in 2002 , limited the Summer Games program to a maximum of 28 sports , 301 events , and 10 @,@ 500 athletes . Three years later , at the 117th IOC Session , the first major program revision was performed , which resulted in the exclusion of baseball and softball from the official program of the 2012 London Games . Since there was no agreement in the promotion of two other sports , the 2012 program featured just 26 sports . The 2016 and 2020 Games will return to the maximum of 28 sports given the addition of rugby and golf . 

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 In 2001 the International Olympic Committee ( IOC ) and the International Paralympic Committee ( IPC ) signed an agreement which guaranteed that host cities would be contracted to manage both the Olympic and Paralympic Games . This agreement was to remain in effect until the 2012 Summer Olympics , but was extended , encompassing all Summer and Winter games up until the 2020 Summer Olympics . 
