In the context of science and mathematics, "observables" refer to properties or quantities that can be measured or observed in a system. For example, in physics, observables include variables like position, momentum, and energy. These measurements provide valuable information about the state of a system and can be used to make predictions. In quantum mechanics, observables are represented by operators that act on the state of a system. When a measurement is made, the observable yields a specific value, known as an eigenvalue. This process is fundamental to understanding the behavior of particles and systems at the quantum level.