One original, and continuing, source of interest in large numbers is observation of the natural world, such as trying to count the stars on a clear night or contemplation of the number of grains of sand on the seashore. Indeed, a search of the internet quickly reveals many discussions of the relative numbers of stars and grains of sand. Big numbers arise both within arithmetic, as a system of formal numerical structures, and in applications of mathematics as a way of describing, through counting and measuring, aspects of the physical and social worlds people inhabit. While the main emphasis of this article is on large numbers arising in social and political contexts, the system of the natural numbers, and the history of thinking about large numbers within it, are first briefly illustrated. The rest of the article concentrates on ways to provoke people get a sense of very large numbers, and their implications, reflecting aspects of the sociopolitical world today. (Contains 1 note.)