Why does brake pedal sound like air?

If the brake pedal sounds like air when pressed, it could indicate a problem with the brake system, such as air trapped in the brake lines or a leak in the brake booster. This can cause a hissing or whooshing noise as air escapes or is compressed. Additionally, a failing brake booster may create similar sounds due to a vacuum leak. It's essential to have the brake system inspected by a professional to ensure proper functioning and safety.