Video bitrate is a crucial factor in determining video quality and file size. It refers to the amount of data processed per unit of time in a video stream, typically measured in bits per second (bps). Higher bitrates generally indicate better quality but larger file sizes. Bitrate can be variable or constant, affecting compression efficiency and playback smoothness. Good quality video typically requires a bitrate of around 3,000 to 6,000 Kbps for 1080p resolution, while higher resolutions like 4K may need over 15,000 Kbps for optimal quality.