Hydra

Hydra ( mythology), a creature from Greek mythology
Freshwater polyps, family Hydridae, only with genus Hydra, from the tribe of cnidarians
Hydra of Mallorca, Spain in 2003 gefundes two-headed copy of the hooded snake

Geography, and Astronomy:

Hydra (Cape), in ancient times, a cape on the Gulf of Elaea in the Asia Minor Äölis
Hydra (Algiers ), a neighborhood in Algiers ( Algeria), with nearly 60,000 inhabitants
Hydra ( island), a Greek island in the Aegean Sea
Hydra ( moon), a moon of the dwarf planet Pluto

Companies, brands, products, vehicles:

Hydra (rocket), an American unguided air - to-ground missile
Hydra ( Battleship ), Greek battleship ( 1889-1918 )
Hydra ( speed boat), speed boat of the German Kriegsmarine
Hydra (software ), a cracking program to decrypt passwords
HYDRA Game Development Kit, a video game console, based on the Propeller chip
Hydra ( Production Management ), a system for collecting operational data production
Hydra (Protocol ), a protocol for bi-directional data transmission in mailbox systems and FidoNet
Hydra ( chess), a chess computer
Hydra, code name for the Microsoft Windows NT 4.0 Terminal Server Edition

As well as:

Hydra ( club ), a German advocacy of prostitutes
An EU-funded research project on Ambient Intelligence
An album by the American rock band Toto ( band )
Hydra, radio call, or part thereof, for units of the dike associations; is partially used as a general radio call for units of civil protection and disaster relief in Germany
A prose work of the writer Heiner Müller: Herakles 2 or the Hydra
A book by Paul Kirchhof: The Law of Hydra. Give the people back their state.
A criminal organization in the book "Limit" by Frank Schätzing
A space cruiser in the German TV series Space Patrol from the 60s
A terrorist organization by the Nazis during World War II in the comic and movie Captain America