On-screen display

An on-screen display (abbreviated OSD) is an image superimposed on a screen picture, commonly used by modern televisions, VCRs, and DVD players to display information such as volume, channel, and time.In the past, most adjustments on TVs were performed by means of analog controls, like potentiometers and switches. This is still used in modern monochrome portable TVs. After remote controls were invented, digital adjustments became common. They needed an external display, which was LED, LCD, or VFD based. Including this display increased manufacturing costs.
See more at Wikipedia.org...