✎ This article/section is a stub — some half-sorted notes, not necessarily checked, not necessarily correct. Feel free to ignore, or tell me about it.
7-segment, 9-segment display, 14-segment, and 16-segment display. If meant for numbers will be a dot next to each (also common in general), if meant for time there will be a colon in one position.
These are really just separate lights that happen to be arranged in a useful shape.
Very typically LEDs (with a common cathode or anode), though similar ideas are sometimes implemented in other display types - notably the electromechanical one, and also sometimes VFD.
Even the simplest, 7-segment LED involves a bunch of connectors so are
often driven multiplexed, so only one of them is on at a time.
often done via a controller that handles that multiplexing for you
Seven segments are the minimal and classical case,
good enough to display numbers and so e.g. times, but not really for characters.
More-than-7-segment displays are preferred for that.
