gNormalizer displays results from the Google books Ngram Viewer above the same quantitative results standardized to a common scale so that chronological relationships among terms with very different frequencies may be easily compared. The normalization used to put all series on a common scale is Feature Scaling in which the range of each frequency series is scaled to be in the range of [0,1].

Enter terms and parameters in the Google interface and watch both graphs appear.

Try some of these pairs: David Bowie, Mott the Hoople;   John Lennon, Yoko Ono;   Betamax, VCR;   atom bomb, h-bomb;   Atkins Diet, Caveman Diet;   AIDS, drug cocktail;   computer, 8088;   terrorism, September 11.