dit

Dit is a term used in Morse code to denote the short signal known as a dot. It contrasts with a dah (dash), the longer signal. In practice, transmissions are described as sequences of dits and dahs. For example, the letter A is dit-dah, and S is dit-dit-dit. In standard timing, a dit lasts one unit of time; a dah lasts three units. The gap between elements within a character is one unit, the gap between letters is three units, and the gap between words is seven units. The term is common in amateur radio, telegraphy, and Morse-code training.

Morse code was developed in the 1830s by Samuel Morse and Alfred Vail and encodes Latin letters and numerals using sequences of short and long signals. The dot-and-dash distinction, with dits and dahs, was chosen to maximize readability under varying conditions and signaling speeds. The system played a crucial role in early telegraphy and later radio communication, remaining a foundational example of efficient, low-bandwidth signaling.

In other contexts, dit appears as a French verb form: dit is the third-person singular present indicative of dire, meaning "he says" or "it is said." The uppercase acronym DIT is used for various terms in technology and administration, such as Department of Information Technology or Digital Imaging Technology, depending on the organization and country. The term dit thus has both a technical meaning within Morse code and broader linguistic or organizational uses in other domains.