An amplifier is an electronic device that increases the power of a signal. It takes a weak electrical signal and boosts it, making it stronger without altering its original content. Amplifiers are commonly used in audio equipment, such as speakers and microphones, to enhance sound quality and volume. There are various types of amplifiers, including operational amplifiers and power amplifiers, each designed for specific applications. They are essential in many devices, from guitars to televisions, ensuring that signals are transmitted clearly and effectively over distances or through different media.