With those instruments, the rover is analyzing powdered samples that are drilled from the rocks and soil, to discover the history of the Red Planet. Many rock samples that the rover took have been drilled from Gale crater, which used to be a lake in the distant past. They were found to contain key requirements for life, organic carbon (a carbon bound to hydrogen atom), which is a necessary condition for all known forms of life to develop.
During his exploration, the “little” rover, which is about 9 feet and 10 inches long by 9 feet and 1 inch wide (3 meters by 2.8 meters) and about 7 feet high (2.1 metters) and weights 2,000 lbs. (900 kg), has also taken a few interesting pictures of Mars, but on top of that, quite an impressive collection of selfies that would rival a teenager's collection. Its time on Mars was not always just spent taking nice pictures and making amazing discoveries, though. Our metal hero also faced a few challenges, with drill malfunctions, system glitches, damage to its wheels, and orientation troubles.
Here is a happy birthday to you, Curiosity and to the many discoveries that you have brought us, humans.