20161021

20161021 is the numeric date form representing October 21, 2016, written in the year–month–day order often used in data systems. It is commonly employed in filenames, database keys, and software to ensure consistent chronological sorting and unambiguous storage across locales.

Historically, October 21 is associated with several notable events. The Battle of Trafalgar, a decisive naval engagement during the Napoleonic Wars, took place on October 21, 1805, as the British fleet under Admiral Horatio Nelson defeated the combined French and Spanish fleets; Nelson died during the battle.

The particular date 2016-10-21 does not denote a single globally defining event. Instead, it marks a day on which various regional or sectoral events occurred, including news, cultural releases, or anniversaries. In contrast to dates tied to a widely recognized milestone, 2016-10-21 is primarily a chronological label used in record-keeping.

From a data perspective, 20161021 is valued for its lexicographic sortability and clarity across different language conventions. It exemplifies the YYYYMMDD format standardized in many systems and is compatible with ISO 8601 usage when separators are omitted.

See also: ISO 8601, Gregorian calendar, date formats, Trafalgar, October 21.