The first Summer Olympics was in April 1896 in Athens, Greece, featuring 241 participants from 14 countries competing in 43 events across 10 sports.
More than a century later at the Rio Games, there are more than 11,000 participants from 207 countries competing in 306 events across 42 sports.
Needless to say, a lot has changed. Sprinters and swimmers are faster, weightlifters are stronger, world records have been set and broken, and athlete attire has certainly evolved.
In other cases, however, a lot remains the same – basketball is still putting a ball through a hoop, wrestling is still two guys grappling, and rugby is still a bunch of guys swarming around a ball. .
Here are photos from 11 events from past Olympics compared to what those same events look like in Rio.
Use the slider to reveal more of less of each photo.
In 1896, Germany's Carl Schuhmann won at the first modern International Summer Olympic Games held at the Panathinaiko Stadium in Athens, Greece. Schuhmann was a part of an 11-man German gymnastics team that had two first-places finishes in Athens. Schuhmann also competed in the long jump, triple jump, shot put, wrestling, and weightlifting (90 kg) at these Games.
In 2016, North Korea's Ri Se Gwang won gold in the men's individual vault with a score of 15.691. It was his first Olympic medal.
With just three teams — the US, France, and Romania — competing at the 1924 Paris Olympics, all three played each other before the final. Here, the US and Romania faced off, with the Americans winning, 37-0, before going onto the final against France. The Americans won the gold medal match against France, 17-3. Until this year, rugby had not been at the Olympics since those 1924 Paris Games.
In Rio, 12 teams competed in rugby sevens. Here, Great Britain's Sam Cross offloads to Dan Bibby during a semifinal match against South Africa. Great Britain advanced to the final with a 7-5 win, but fell to Fiji in the gold-medal match, 43-7.
Men’s high jump
At the 1932 Los Angeles Games, American Bob Van Osdel won silver, finishing behind Canadian Duncan McNaughton, who won gold by clearing 1.97 meters. The two were teammates at the University of Southern California. When McNaughton's gold medal was stolen in 1933, Van Osdel made a mold of his silver medal, poured gold into it, and shipped it to McNaughton as a replacement.
In Rio this summer, Canada's Derek Drouin won by clearing 2.38 meters. It was his second Olympic medal after winning bronze in the high jump at the 2012 London Games.
Though construction of the Los Angeles Memorial Coliseum was completed in 1923, its capacity was expanded to hold more than 101,000 for the 1932 Olympics. The Olympic Cauldron was also added for those Games, the first of two Los Angeles has hosted. Here, doves were released as a part of the Opening Ceremony on July 30.
In 2016, the Rio Opening Ceremony was held at Maracanã Stadium, which holds more than 78,000 people. It opened in 1950 to host the FIFA World Cup. Renovations came in 2000, 2006, and 2013, ahead of the 2014 FIFA World Cup.
In 1932, Buster Crabbe of the United States, shown nearest the camera, won the gold medal in the 400-meter freestyle, setting an Olympic record with a time of 4 minutes, 48.4 seconds, which was about 1.5 seconds short of the world record. Crabbe went on to pursue an acting career, starring in the serial Flash Gordon in 1936.
In 2016, Mack Horton of Australia won gold in the 400 free in 3:41.55. The Olympic record in the 400 free is 3:40.14, set at the 2012 London Games by China's Sun Yang.
After the 1940 and 1944 Games were canceled due to World War II, London played host in 1948. It was the second of three times the city would host a Summer Games. Here, contestants in the men's 10,000 meter race ran in Wembley Stadium. Czechoslovakia's Emil Zátopek won gold and set an Olympic record with a time of 29:59.6. Zátopek also won silver in the 5,000 meters in London. He went on to repeat in the 1952 Games and added gold in the 5,000 meters and the marathon at the Helsinki Games, becoming the only runner to win gold in that trio of events at the same Games.
In 2016, Mohamed Farah of Great Britain won the 10,000 meter race in a time of 27:05.17. The Olympic record in the 10,000 meters is 27:01.17, set by Ethiopia's Kenenisa Bekele at the 2008 Beijing Games.
German heavyweight wrestler Willi Waltner, kneeling in front, lost a freestyle wrestling bout against Russian Arsen Mekokishvili at the Helsiniki Games on July 21, 1952. Mekokishvili went on to win gold in the heavyweight division.
In Rio this summer, Armenia's Artur Aleksanyan defeated Cuba's Yasmany Cabrera to win gold in the men's Greco-Roman 98 kg class. It was the 24-year-old's second Olympic medal, his first coming at the 2012 London games, a bronze in the 96 kg class.
Celtics legend Bill Russell dropped 13 points against the Soviet Union in the gold medal game of the Melbourne Olympics on Dec. 1, 1956. The Americans won, 89-55, earning their fourth gold medal. Russell had been drafted by the Celtics earlier that year and captained Team USA through the 1956 Olympics, averaging 14.1 points as the Americans went 8-0 throughout the tournament, before joining the Celtics after the Olympics were over.
This summer, the Americans are going for their third straight gold medal and the program's 15th overall gold. Through pool play, Kevin Durant averaged 16.8 points and 4.4 rebounds per game.
Great Britain's Bill Hoskyns and Witold Woyda of Poland, right, are shown in action during their bout in the Summer Games in Rome on Aug. 30, 1960. Woyda won the bout, 5-3. Though neither Hoskyns nor Woyda captured an individual medal at the 1960 games, Hoskyns won a silver with Great Britain in team epee and Woyda went on to win four Olympic medals: a team silver at the 1964 and 1968 Games, and a team gold and individual gold in the 1972 Games.
In Rio this summer, France's Yannick Borel competed with Enrico Garozzo of Italy in team epee competition. France topped Italy, 45-31, to win gold. It was Borel's first Olympic medal.
Czechoslovakia's Vera Caslavska won gold on the long-horse vault at the 1964 Tokyo Olympics on Oct. 22, 1964. Larissa Latynina of the Soviet Union and Germany's Birgit Radochia tied for second place. Caslavska won three gold medals and a silver in Tokyo: individual all-around, vault, balance beam, and team (silver). She went on to win four golds and two silvers at the 1968 Mexico City Games. She also won a team silver at the 1960 Rome Games.
In 2016, Simone Biles won gold on vault (pictured) as well as three other golds (individual all-around, floor, team) and a bronze (balance beam). Here, she is flanked by silver medalist Maria Paseka of Russia and Switzerland's Giulia Steingruber.
The Soviet Union had 6-foot-11-inch Iuliyaka Semenova on its side in the 1976 Montreal Games. Though the US had women's basketball legends such as Ann Meyers (6) — later Ann Meyers Drysdale — and Patricia Head (14) — later Pat Summitt — the US came up short against the Soviets, losing, 112-77. The Americans went 3-2 in the tournament and settled for silver.
This summer, however, is a different story. The Americans have their sights set on a sixth straight gold medal and their eighth overall. With 6-foot-8-inch Brittney Griner in the fold, the US cruised through pool play and the quarterfinals, putting up 100 or more points in five of its first six games.
Follow Rachel G. Bowers on Twitter @RacheGBowers.