A glass fuse is a safety device used in electrical circuits to protect against overloads and short circuits. It consists of a thin wire enclosed in a glass tube. When too much current flows through the wire, it heats up and melts, breaking the circuit and preventing damage to electrical components. Glass fuses come in various sizes and ratings, making them suitable for different applications. They are commonly found in household appliances, automotive systems, and electronic devices. Replacing a blown glass fuse is usually straightforward, but it's essential to use the correct type to ensure safety and proper function of the circuit.