The history of the studies done on photosynthesis dates back into 17th century with Jan Baptist van Helmont, a Belgian chemist, physiologist and physician. It is a process used by plants and other organisms to convert light energy to chemical energy. He performed 5 year experiment involving a willow tree which he planted in a pot with soil and placed in a controlled environment.
Photosynthesis comes from two words, "photo" means "light" and "synthesis" means "to make". Photosynthesis evolved as a way for the first living cells to make their own nutrition from commonly occurring natural elements of air, water and light.
Afterwards, in 18th century, Jan Ingenhousz, a Dutch physician, chemist and biologist discovered how plants convert light to energy. He was also credited with discovering the plants similar to animals undergo the cellular respiration process.