The modern Olympic Games or Olympics are leading international sporting events 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 the world's foremost sports competition with more than 200 nations participating. The Olympic Games are normally held every four years, alternating between the Summer and Winter Olympics every two years in the four-year period.

Their creation was inspired by the ancient Olympic Games, held in Olympia, Greece from the 8th century BC to the 4th century AD. Baron Pierre de Coubertin founded the International Olympic Committee (IOC) in 1894, leading to the first modern Games in Athens in 1896. The IOC is the governing body of the Olympic Movement, with the Olympic Charter defining its structure and authority.

The evolution of the Olympic Movement during the 20th and 21st centuries has resulted in several changes to the Olympic Games. Some of these adjustments include the creation of the Winter Olympic Games for snow and ice sports, the Paralympic Games for athletes with disabilities, the Youth Olympic Games for athletes aged 14 to 18, the five Continental games ( Pan American, African, Asian, European, and Pacific), and the World Games for sports that are not contested in the Olympic Games. The IOC endorses the Deaflympics and the Special Olympics. The IOC has needed to adapt to a variety of economic, political, and technological advancements. The abuse of amateur rules by Eastern Bloc nations prompted the IOC to shift away from pure amateurism, as envisioned by Coubertin, to the acceptance of professional athletes participating at the Games. The growing importance of mass media has created the issue of corporate sponsorship and general commercialization of the Games. World Wars led to the cancellation of the 1916, 1940, and 1944 Olympics; large-scale boycotts during the Cold War limited participation in the 1980 and 1984 Olympics, and the 2020 Olympics were postponed until 2021 as a result of the Covid-19 pandemic.

Tokyo Olympics started from 23rd July 2021.

The Olympic Movement consists of international sports federations (IFs), National Olympic Committees (NOCs), and organising committees for each specific Olympic Games. As a decision making body, the IOC is responsible for choosing the host city for each Games, and organises and funds the Games according to the Olympic Charter. The IOC also determines the Olympic programme, consisting of the sports to be contested at the Games. There are several Olympic rituals and symbols, such as the Olympic flag and torch, as well as the opening and closing ceremonies. Over 14,000 athletes competed at the 2016 Summer Olympics and 2018 Winter Olympics combined, in 35 different sports and over 400 events. The first, second, and third-place finishers in each event receive Olympic medals: gold, silver, and bronze, respectively.

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

Ancient Olympics
The Ancient Olympic Games were religious and athletic festivals held every four years at the sanctuary of Zeus in Olympia, Greece. Competition was among representatives of several city-states and kingdoms of Ancient Greece. These Games featured mainly athletic but also combat sports such as wrestling and the pankration, horse and chariot racing events. It has been widely written that during the Games, all conflicts among the participating city-states were postponed until the Games were finished. This cessation of hostilities was known as Olympic peace or truce. This idea is a modern myth because the Greeks never suspended their wars. The truce did allow those religious pilgrims who were travelling to Olympia to pass through warring territories unmolested because they were protected by Zeus. The origin of the Olympics is shrouded in mystery and legend; one of the Heracles who first called the Games "Olympic" and established the custom of holding them every four years. The myth continues that after Heracles completed his twelve labours, he built the Olympic stadium as an honor to Zeus. Following its completion, he walked in a straight line for 200 steps and called this distance a "station", which later became a unit of distance. The most widely accepted inception date for the Ancient Olympics is 776 BC; this is based on inspections, found Olympia, listing the winners of a footrace held every four years starting in 776 BC. The Ancient Games featured running events, a pentathlon (consisting of a jumping event, discus and javlin throws, a foot race, and wrestling), boxing, wrestling, pankration, and equestrian events. Tradition has it that Coroebus, a cook from the city of Elis, was the first Olympic champion.

The Olympics were of fundamental religious importance, featuring sporting events alongside ritual sacrifices honouring both Zeus (whose famous statue by Phidias stood in his temple at Olympia) and Pelops, divine hero and mythical king of Olympia. Pelops was famous for his chariot race and king Oenomaus of Pisatis. The winners of the events were admired and immortalised in poems and statues. The Games were held every four years, and this period, known as Olympiad, was used by Greeks as one of their units of measurement. The Games were part of a cycle known as the Panhellenic Games, which included the Pythian Games, the Nemean Games, and the Isthmian Games.

The Olympic Games reached the height of their success in the 6th and 5th centuries BC, but then gradually declined in importance as the Romans gained power and influence in Greece. While there is no scholarly consensus as to when the Games officially ended, the most commonly held date is 393 AD, when the emperor Theodosius I decreed that all pagan cults and practices be eliminated. Another date commonly cited is 426 AD, when his successor, Theodosius II, ordered the destruction of all Greek temples.

Mordern Games
Forerunners
Various uses of the term " Olympic" to describe athletic events in the modern era have documented since the 17th century. The first such event was the Cotswold Games or "Cotswold Olimpick Games", an annual meeting near Chipping Campden, England, involving various sports. It was first organized by the lawyer Robert Dover between 1612 and 1642, with several later celebrations leading up to the present day. The British Olympic Association, in its bid for the 2012 Olympic Games in London, mentioned these games as "the first stirrings of Britain's Olympic beginnings".

L'Olympiade de la Republique, a national Olympic festival held annually fro 1796 to 1798 in Revolutionary France also attempted to emulate the ancient Olympic Games. The competition included several disciplines from the ancient Greek Olympics. The 1796 Games also marked the introduction of the metric system into sport.

Revival
Greek interest in reviving the Olympic Games began with the Greek War of Independence from the Ottoman Empire in 1821. Evangelos Zappas, a wealthy Greek-Romanian philanthropist, first wrote to King Otto of Greece, in 1856, offering to fund a permanent revival of the Olympic Games. Zappas sponsored the first Olympic Games in 1859, which was held in Athens city square. Athletes participated from Greece and the Ottoman Empire. Zappaas funded the restoration of the ancient Panathenaic Stadium so that it could host all future Olympic Games. 

The stadium hosted Olympics in 1870 and 1875. Thirty thousand spectators attended that Games in 1870, through no official attendance records are available for the 1875 Games. In 1890, after attending the Olympian Games of the Wenlock Olympian Society, Baron Pierre de Coubertin was inspired to found the International Olympic Committee (IOC). Coubertin built on the ideas and work of Brookes and Zappas with the aim of establishing internationally rotating Olympic Games that would occur every four years. He presented these ideas during the first Olympic Congress of the newly created international Olympic Committee. This meeting was held from 16 to 23 June 1894, at the University of Paris. On the last day of the Congress, it was decided that the first Olympic Games to come under the auspices of the IOC would take place in Athens in 1896. The IOC elected the Greek writer Demetrius Vikelas as its first president.

Changes and Adaptions
After the success of the 1896 Games, the Olympics entered a period of stagnation which threatened its survival. The Olympic Games held at the Paris Exposition in 1900 and the Louisiana Purchase Exposition at St. Louis in 1904 failed to attract much participation or notice. Of the 650 athletes in the 1904 Olympics, 580 were American; the winner of the marathon was later disqualified upon discovery of a photograph of him riding in a car during the race. The Games rebounded with the 1906 Intercalated Games (so-called because they were the second Olympics to take place within the third Olympiad), which were held in Athen. These Games attracted a broad international field of participants and generated a great deal of public interest, marking the beginning of a rise in both the popularity and the size of the Olympics. The 1906 Games were officially recognised by the IOC at the time (although not any longer), and no Intercalated Games have been held since.

Winter Games
The Winter Olympics was created to feature snow and ice sports that were logistically impossible to hold during the Summer Games. Figure Skating (in 1908 and 1920) and Ice Hockey (in 1920) were featured as Olympic events at the Summer Olympics. The IOC desired to expand this list of sports to encompass other winter activities. At the 1921 Olympic Congress in Lausanne, it was decided to hold a winter version of the Olympic Games. 

References;
1. Olympic Games