Why do you think that historians use the word "revolution" to describe important changes in agriculture? How did the Green Revolution and other agricultural revolutions change the lives of billions of people?

The word revolution is used to show the dramatic effective change by adopting certain policies and practices and thus used in describing the changes that occur in agriculture, as well.

Green revolution affected billions of lives by improving the crop yield due to the development of disease resistant crop cultivars and use of insecticides as well as pesticides, which led to tons of productivity and hunger and poverty was controlled. This occurred in 1930 to 1960, and Norman Borlaug, the father of Green Revolution led its initiatives and eventually won Noble Peace Prize in 1970.