The quality of a car isn’t determined by how fast it can go—it’s about whether it can stop safely, no matter how fast it’s moving. And when it comes to stopping a car, one component stands out above all others: the car’s brakes (also known as braking systems). Braking systems are broadly categorized into two types: disc brakes (also called brake discs) and drum brakes. Typically, small vehicles with seven seats or fewer—like compact cars—are equipped with disc brakes, while larger vehicles such as buses and heavy-duty trucks usually rely on drum brakes for their braking needs.

What is a disc brake?
Disc brakes, as the name suggests, consist of stationary brake calipers (equipped with brake pads underneath) that clamp down on a rotor—mounted coaxially with the wheel—to create friction, thereby slowing and eventually stopping the vehicle. Disc brakes are a quintessential example of static braking systems. Typically, the caliper features two opposing brake pistons; however, high-performance supercars or premium vehicles often equip 4-piston calipers, while some top-tier models even boast 6-piston calipers. Naturally, larger calipers require correspondingly bigger brake pads and rotors to enhance braking efficiency.

What are the advantages and disadvantages of disc brakes?
The advantages of disc brakes are:
1. The structure is relatively simple, consisting of a brake piston, brake caliper, brake pads, and brake disc, making it easy to maintain.

2. It features excellent heat dissipation performance, making it resistant to thermal fade even under high-frequency braking, thus preventing brake failure caused by brake degradation.

3. The environment has a minimal impact on braking; in fact, rainy conditions have such a negligible effect on the brake system that it can be safely ignored. However, tire slippage is completely beyond the control of the braking system.

The disadvantages of disc brakes are:
1. Without an automatic tightening mechanism, it requires significant braking force, or a hydraulic piston device with even greater power to complete the braking process.

2. Disc brakes have a smaller friction area between the brake pads and the brake disc, resulting in relatively lower braking force (commonly used in small, lightweight vehicles).

3. The handbrake mechanism is not easy to install and requires the addition of a separate drum-brake-equipped handbrake system.

4. The brake pads show significant wear, which may lead to more frequent replacement needs.

How to maintain it?
1. Check the brake fluid level—top up immediately if it’s too low—and inspect the fluid for cleanliness, as heavily contaminated brake fluid can significantly reduce braking performance.

2. Check the brake pads—they are wear-and-tear components. Typically, you should regularly inspect their thickness after driving 30,000 kilometers, and consider replacing them around 60,000 kilometers.

What is a drum brake?
Two semi-circular brake pads are installed inside the wheel hub, and a "lever principle" is used to push the brake pads against the inner surface of the brake drum, creating friction. Simply put, drum brakes rely on stationary brake pads inside the brake drum, which rub against the rotating brake drum as the wheel turns, generating friction that slows down or brings the wheel to a complete stop.

What are the advantages and disadvantages of drum brakes?
The advantages of drum brakes are:
1. Featuring an automatic tightening mechanism, the braking system can operate at lower oil pressure or utilize a brake drum that is significantly smaller in diameter than the brake disc.

2. Vehicles equipped with drum brakes are easy to install a handbrake system on.

The disadvantages of drum brakes are:
1. Easily prone to thermal degradation, it cannot handle continuous high-frequency braking, often leading to brake failure.

2. The braking system responds slowly, and the brake pedal feel is difficult to control, making it challenging to perform high-frequency braking maneuvers.

3. The structure is relatively complex and not easy to repair or maintain.

4. Highly susceptible to environmental factors, drum brakes can experience brake fade or failure if water enters them on rainy days.