Mars Pathfinder was a robot that was sent to explore Mars, which is a planet that is far away from Earth. The robot was made by really smart people who wanted to learn more about Mars and see if it was a good place for people to visit.
The robot was really cool because it had a camera that could take pictures of Mars and send them back to Earth. It also had a special instrument that could check the weather on Mars and see how hot or cold it was.
Mars Pathfinder was sent to Mars on a spaceship, which is like a really big rocket that can travel through space. When it got to Mars, it landed on the ground using a parachute and airbags.
After it landed, Mars Pathfinder started exploring the surface of Mars. It drove around and took lots of pictures and checked the weather. It also found some really cool rocks and soil.
The robots' mission was to learn more about Mars and see if there was any evidence that there was ever water on the planet. Water is really important for life, so if there was water on Mars, that might mean that there could be life there too.
Mars Pathfinder was a really important mission because it helped scientists learn more about Mars and prepare for future missions to explore the planet even more.