Brake fluid is a crucial hydraulic fluid used in vehicle braking systems, enabling effective transfer of force from the brake pedal to the brake components. It plays a vital role in ensuring safety and performance by maintaining consistent braking power under various conditions. Brake fluids are categorized by their DOT ratings, such as DOT 3, DOT 4, and DOT 5.1, which indicate their boiling points and chemical composition. DOT 3 is suitable for everyday passenger vehicles, while DOT 4 is used in more demanding applications, offering higher boiling points to withstand extreme temperatures. DOT 5.1, compatible with glycol-based fluids, is designed for high-performance and heavy-duty vehicles, providing superior thermal stability and performance. Proper maintenance and timely replacement of brake fluid are essential for optimal braking performance and safety.