Apollo refers to the Apollo space program, a series of spaceflight missions conducted by NASA between 1961 and 1975, with the goal of landing a man on the Moon and returning him safely to Earth. The Apollo program is considered to be one of the greatest achievements in human history, and it was the first and so far the only human mission to land on the Moon.
The Apollo program consisted of several manned and unmanned missions, culminating in the Apollo 11 mission in 1969 when the astronaut Neil Armstrong famously declared "That's one small step for man, one giant leap for mankind" as he became the first human to step on the lunar surface. Other manned Apollo missions include Apollo 12, Apollo 14, Apollo 15, Apollo 16, and Apollo 17, which also successfully landed on the Moon.
The Apollo program was not just a mission to land on the Moon but also a technological achievement, which developed many new technologies and innovations such as the Lunar Module, a spacecraft built specifically to land on the lunar surface, and the Saturn V, the most powerful rocket ever built at the time. These innovations not only made the Apollo program a success but also laid the foundation for future space exploration.