While sundials and water clocks existed for millennia, the first mechanical clocks began appearing in European monasteries and town squares around 1300. These clocks used a weight-driven mechanism and an 'escapement' to regulate the release of energy, allowing them to keep time without the need for flowing water. The invention changed the fundamental rhythm of human life, shifting society from 'natural time' (determined by the sun) to 'clock time.' This was essential for the coordination of urban life, complex trade, and eventually industrial labor. Early clocks often lacked faces and simply rang bells (the word 'clock' comes from the Latin 'clocca,' meaning bell). The precision of these machines improved significantly with the invention of the pendulum by Christiaan Huygens in 1656, making timekeeping accurate enough for scientific observation and navigation.