Since ancient times, people have attempted to reproduce the appearance and actions of living beings, with varying degrees of verisimilitude. We have chosen not to discuss ancient, medieval, and Renaissance automata here because we believe that their mechanics are not satisfactorily documented and that the use of cams cannot be properly verified. In fact, during the second half of the eighteenth century, cams experienced an unexpected and extraordinary advance in quality and complexity. Thanks to some automata builders, cams were used to their full potential and achieved spectacular performances. A famous creator and builder of automata is J. de Vaucanson, known for his digesting duck and many other automata. Another famous automaton is the tympanum player designed by P. Kintzing for Queen Marie Antoinette. The most famous automata are undoubtedly the three androids built by the watchmakers Jaquet-Droz, father and son, and their assistant J-F Leschot. The androids are known as the Writer, the Musician and the Draftsman. Complex cam mechanisms create movements and postures that mimic those of humans, inspiring admiration from their contemporaries and beyond. Other automata, such as those created by H. Maillardet and F. von Knaus, also deserve to be remembered. The most glorious period of mechanical automata came as the Industrial Revolution was about to begin. Knowing how to make and use cams may have laid the groundwork for their later use in the next phase of automation.