19171993

19171993 is a numeric string formed by concatenating the calendar years 1917 and 1993. In encyclopedic and bibliographic practice, a lifespan is commonly presented with a separator, most often as 1917–1993, to indicate that a person was born in 1917 and died in 1993. The unbroken form 19171993 is less common and can cause ambiguity outside of a specific data context.

Two principal interpretations apply. It may denote the lifespan of an individual when paired with appropriate context, or it may indicate a historical period stretching from the year 1917 to 1993. When used as a date range in lists, infoboxes, or catalogs, it is often clearer to separate the dates with a dash, en dash, or the words birth and death.

Ambiguities may arise in databases, file names, or search queries because the same digits could encode different data types, such as a catalog identifier or a shorthand for a time span. Standard practice in library and archival metadata is to normalize such values to explicit forms like 1917–1993 or 1917 to 1993 CE.

Contextually, the period from 1917 to 1993 covers a broad swath of the 20th century, including major geopolitical and social changes, global conflicts, decolonization, and the late Cold War era, ending around the dissolution of the post–Cold War order and related reforms in the early 1990s.