4K video refers to a resolution of approximately 3840 x 2160 pixels, which is four times the pixel count of 1080p video. This higher resolution provides greater detail and clarity, making images appear sharper and more lifelike. The term "4K" is commonly used in the context of televisions, monitors, and streaming services that support this format. As technology advances, more content is being produced in 4K, allowing viewers to enjoy a more immersive experience in movies, video games, and online videos.