"That's one small step for man, one giant leap for mankind." What does it mean?

This sentence means: Although I only took a small step after landing on the moon, walking on the moon for the first time was a huge breakthrough for mankind, so this is a giant step for mankind. .

These words were spoken when Armstrong landed on the lunar surface in the Eagle landing module on July 20, 1969. As an astronaut, this is indeed a small step for him. But this small step is the crystallization of human wisdom and strength, and a huge progress for mankind. This big step means that mankind has taken another big step towards understanding nature.

Extended information:

This sentence was said by American astronaut Armstrong. The following is a brief introduction to him:

Neil Alden· Armstrong (August 5, 1930 - August 25, 2012), American astronaut, test pilot, naval pilot and university professor.

While serving with NASA, Armstrong became the first astronaut to set foot on the moon on July 21, 1969, and the first to leave footprints on an extraterrestrial body. members of the human race. Armstrong's first space mission was Gemini 8. During this mission, he and David Scott performed the first orbital docking in history.