A 7-segment display is an electronic display device used for displaying decimal numerals. It consists of seven individual segments (labeled A through G) arranged in a rectangular fashion to form the number 8. Each segment is typically an LED, and by illuminating different combinations of these segments, the display can represent the digits 0 through 9. These displays are widely used in digital clocks, calculators, and other devices requiring numerical output due to their simplicity and ease of readability.