A speaker is an electroacoustic transducer that converts electrical audio signals into corresponding sound waves. A typical speaker consists of several key components:

Diaphragm (Cone): This is the surface that produces sound waves by vibrating back and forth. It is typically made of a lightweight and rigid material like paper, plastic, or metal.
Voice Coil: A cylindrical coil of wire that is attached to the diaphragm. When an audio signal (alternating current) passes through the voice coil, it generates a magnetic field that interacts with the permanent magnet, causing the voice coil and diaphragm to vibrate.
Spider: A corrugated or semi-circular suspension component that centers the voice coil and allows it to move in and out while keeping it aligned with the permanent magnet.
Surround (Suspension): A flexible, corrugated material that allows the diaphragm to move while providing an airtight seal between the front and back of the speaker.
Magnet: A permanent magnet, usually made of ferrite or a rare-earth alloy, that provides a static magnetic field for the voice coil to interact with.
Basket (Frame): The rigid outer frame that holds all the speaker components together and provides structural support.
Dustcap: A protective cover in the center of the diaphragm that prevents dust and debris from entering the voice coil area.
Terminals: The connection points where the speaker wires are attached to receive the audio signal from the amplifier.