Keyless Works in watchmaking refers to a system that allows a watch to be wound and set without the use of a separate key. This mechanism involves the use of a winding stem, which both winds the watch and sets the time, date, and other functions depending on its position. The invention of Keyless Works marked a significant advancement in watchmaking, as it replaced the need for an external key, simplifying the process of winding and setting watches. This innovation is attributed to Adrien Philippe, who developed the modern form of sliding pinion keyless work in 1844, leading to the ease of use that modern watch enthusiasts enjoy today.