A chronometer is a precise timekeeping device designed to measure time accurately, especially in challenging conditions. Originally developed for navigation at sea, it helps sailors determine their longitude by comparing the local time with the time at a known location. This accuracy is crucial for safe and effective maritime travel. Today, chronometers are often used in watches and clocks, certified by organizations like the COSC (Contrôle Officiel Suisse des Chronomètres) to ensure their precision. These timepieces are not only functional but also represent a blend of craftsmanship and technology, making them highly valued by collectors and enthusiasts alike.