Words come and go. Concepts drop in and out of favour. The names we call things change. Google Books now offers you to chance to plot the popularity of words - or names or phrases - in its vast corpus of 5 million digitised books. The tool is called the Ngram Viewer, and it is not only free to use - it is simple, and fun.

Information is beautiful has run various experiments with the tool already - such as comparing 'chicken' and 'egg', and 'Plato' and 'Aristotle'. Just enter the words or phrases you want to compare, separated by commas, choose your date range (up to 500 years), select your corpus of choice, e.g. English, British English, and then click Search lots of books.

Tennis or cricket, anyone?