UDF

UDF may refer to:

Computing

• Universal Disk Format, an operating-system-independent file system commonly used on DVD and other digital media
• Uniqueness Database File, a Windows XP Professional configuration text file
• User-defined function, a function provided by the user of a program or environment

Organisations

• United Dairy Farmers, an American chain of ice cream shops

Politics

• Ulster Defence Force, a loyalist paramilitary in Northern Ireland
• Union of Democratic Forces (disambiguation), several political parties
  • Union of Democratic Forces (Bulgaria) (СДС), a political party in Bulgaria
• Union pour la Démocratie Française (Union for French Democracy), a centrist French political party
• United Democratic Forces (ОДС), an electoral alliance in Bulgaria
• United Democratic Forces of Belarus, a coalition of political parties participating as the main opposition group during the 2006 presidential election
• United Democratic Front (disambiguation), several political parties:
  • United Democratic Front (South Africa), a former anti-Apartheid movement in South Africa

Military

• Union Defence Force (disambiguation), several military forces:
  • Union Defence Force (South Africa), the predecessor of the South African Defence Force from 1912 to 1957
  • Union Defence Force (UAE), the armed forces of the United Arab Emirates

Other uses

• Unducted fan, a type of jet engine
• Ultra Deep Field, a view of the distant universe taken in 2004 by the Hubble space telescope
• UHF Direction Finder, a kind of radio direction finding
• Up side down suspension forks, a suspension fork used in motorcycles and mountain bikes