Bandwidth refers to the maximum amount of data that can be transmitted over a network connection in a given amount of time, typically measured in bits per second (bps), kilobits per second (kbps), or megabits per second (Mbps). It represents the capacity of a network link to carry information, much like the width of a highway determines how many cars can travel at once. Higher bandwidth allows for faster data transfer, enabling smoother streaming, quicker downloads, and more efficient online communication.