Encyclopedia

Unschooling Unschooling is a form of education in which learning is based on the student's interests, needs, and goals. It may be alternatively referred to as natural learning, child-led learning, discovery learning, autodidactic learning, or child-directed learning.
Unsigned artist The term unsigned artist is used in the music industry to refer to a singer, songwriter, musician or band that has no affiliation with a record label. Many unsigned artists sell their music and music-related merchandise without the financial support of a record label, while often seeking a recording contract through the recording of demos.
Unsigned band web The Unsigned Band Web is an online music community for unsigned bands to showcase their songs and develop a following. Bands can signup by creating an artist page and uploading songs, videos, images, and band news.
Unsigned code In the video game console business, all console games have to be signed with the code designed by the console maker or the game won't load on the console. Each code is different, PS2 uses a different signed code than the Xbox, for example.
Unsigned Hype Unsigned Hype is a column in the hip-hop magazine The Source devoted to identifying promising new rappers who do not have record deals. Over its existence, it has come to represent a benchmark in rising rappers' careers, and many multiplatinum rap icons were once featured, including the Notorious BIG, Eminem, DMX, 50 Cent, Pitbull, Common, Mobb Deep (appearing as Poetical Prophets), Bishop Lamont, and Proof.
Unsigned Iowa State Highways In Iowa, there are a handful of state highways that are maintained by the state of Iowa, but are not marked as state highways. If marked at all, these unsigned highways are bannered highways -- for example, Iowa 922 is signed as Business U.
Unsinkable aircraft carrier An unsinkable aircraft carrier is a term sometimes used to refer to a geographical or political island that is utilized to extend the power projection of a military force. Because such an entity is capable of acting as an airbase and is a physical landmass incabable of being destroyed, it is in effect an aircraft carrier that cannot be sunk.
Unsolved (TV series) Unsolved is a television programme on stv, which investigates some of the most baffling and intriguing murders in the country, where the killers have never been caught and in some cases, the bodies never found.
Unsolved problems in philosophy Philosophical problems are unlike scientific or mathematical problems. Often, problems in philosophy are refined rather than solved, and there is widespread belief that no philosophical problem is truly "solvable" in the conventional sense.
Unsound Vol. 1 Unsound is the first, and currently only, compilation released in the Unsound series, which replaced Epitaph Records' Punk-O-Rama series. Epitaph chose to change the name of the compilation series due to the fact that the name Punk-O-Rama, especially in its later releases, no longer reflected the wide range of music released on the compilations.
Unspoken rules Unspoken rules are behavioral constraints imposed in organizations that are not voiced or written down. They usually exist in unspoken and unwritten format because they form a part of the logical argument or course of action implied by tacit assumptions.
Unspoken Water In Scottish custom, Unspoken Water was water believed to have healing properties when collected "from under a bridge, over which the living pass and the dead are carried, brought in the dawn or twilight to the house of a sick person, without the bearer’s speaking, either in going or returning".
Unsportsmanlike conduct Unsportsmanlike conduct (or unsporting behaviour, or archaically ungentlemanly conduct) is a term used in most professional sports to refer to a particular player or team who have acted inappropriately and/or unprofessionally in the context of the game. Such behaviour is not necessarily illegal according to the sport in question's rules, but is frowned upon by the vast majority of both players and spectators.
Unsportsmanlike Conduct Unsportsmanlike Conduct is a penalized action in the sport of ice hockey where a player has deemed to cross the threshold of good or fair behavior at the discretion of the referee. This results in the offending player being assessed a 2 minute minor penalty.
Unsprung weight In a ground vehicle with a suspension, the unsprung weight, or more properly, unsprung mass, is the mass of the suspension, wheels or tracks (as applicable), and other components directly connected to them, rather than supported by the suspension. (The mass of the body and other components supported by the suspension is the sprung mass.
Unspunnenfest Unspunnenfest is a festival held in the town of Interlaken, Switzerland, near the old ruin of Unspunnen Castle, in the Bernese Alps, approximately once every ten years. The festival highlights traditional Swiss culture and features competitions of Steinstossen (stone throwing), Schwingen (wrestling) and yodeling.
Unstable Ape Records Unstable Ape Records is an independent record label, originally founded in Tasmania but now based in Melbourne, Australia. Unstable Ape's focus tends primarily towards rock and roll, as opposed to pop, folk or roots.
Unstable molecules Unstable molecules are a piece of fictional technology featured in Marvel Comics. They exist as a configuration of unknown atomic nuclei and electrons that are responsive to certain energized matter around them.
Unstan ware Unstan ware is the name used by archaeologists for a type of finely made and decorated Neolithic pottery from the 4th millennium BC. Typical are elegant, round based bowls with a band of grooved patterning below the rim.
Unstated assumption Unstated assumption is a type of propaganda message which foregoes explicitly communicating the propaganda's purpose and instead states ideas derived from it. This technique is used when a propaganda's main idea lacks credibility, and thus when mentioned directly will result in the audience recognizing its fallacy and nullifying the propaganda.
Unstrange Minds Unstrange Minds (ISBN 0-465-02763-6) is a nonfiction book by anthropologist Roy Richard Grinker about the rise in autism diagnoses throughout the world over the last twenty years. It provides a cultural history of autism and describes the experiences of parents of children with autism in the United States, South Korea, India, and South Africa.
Unstressed vowel An unstressed vowel is the vowel sound that forms the syllable peak of a syllable that has no lexical stress. In many languages, vowel reduction happens when a vowel changes from stressed to unstressed position, i.
Unstructured data Unstructured data or -information refers to masses of (usually) computerized information which do not have a data structure which is easily readable by a machine. Examples of unstructured data may include audio, video and unstructured text such as the body of an email or word processor document.
Unstructured grid An unstructured grid is a tessellation of a part of the Euclidean plane or Euclidean space by simple shapes, such as triangles or tetrahedra, in an irregular pattern. Grids of this type may be used in finite element analysis when the input to be analyzed has an irregular shape.
Unstructured Information Management Architecture Unstructured Information Management Architecture is a framework used to create computer applications that can acquire unstructured information in its raw form and/or its analysis and use in software tools such as databases, search engines, and knowledge management systems.
Unstructured programming Unstructured programming is a programming paradigm where all code is contained in a single continuous block. This is contrary to structured programming, where programmatic tasks are split into smaller sections (known as functions or subroutines) that can be called whenever they are required.
Unstrut-Hainich Unstrut-Hainich is a Kreis (district) in the north of Thuringia, Germany. Neighboring districts are (from the north clockwise) the districts Eichsfeld, Kyffhäuserkreis, Sömmerda, Gotha, Wartburgkreis and the district Werra-Meißner in Hesse.
Unsub (TV series) Unsub was a 1989 television series starring David Soul as a forensic investigator. The show was considered a spiritual ancestor of series like CSI, Without A Trace, The Inside and Criminal Minds (which makes frequent use of the acronym itself).
Unsuccessful nominations to the Supreme Court of the United States Justices of the Supreme Court of the United States are nominated by the President and confirmed by the Senate. Sometimes, the President's choice for the court is rejected by the Senate, sometimes they withdraw under pressure, and sometimes the nominee declines the nomination.
Unsui Manaka Sensei , who also goes by the martial name , has over 40 years of experience in the Japanese arts of kobudo, having started training as a student of Masaaki Hatsumi (Soke of the Bujinkan) at the age of 14 (at this age he had just won a local judo tournament in Japan). As the years passed, Manaka Sensei became the most senior student of Masaaki Hatsumi.
Unsung Unsung is an EP released December 6, 2005 by Christian metalcore group The Chariot. It contains two new songs and four re-worked versions of songs from their debut album Everything Is Alive, Everything Is Breathing, Nothing Is Dead, and Nothing Is Bleeding.
Unsung Hero (magazine) Unsung Hero, also known as Uhero Magazine, was a music magazine publication based out of Gettysburg, Pennsylvania. It was an American magazine devoted to unsigned music and popular culture, centralized in the mid-atlantic region of the United States.
Unsustainable fishing methods Unsustainable fishing methods are ways of catching wild fish that are not considered sustainable in the long term. This could be because they threaten the fish stock itself by overfishing, or because they threaten the environment the fish need to thrive.
Unsymmetrical dimethylhydrazine Unsymmetrical dimethylhydrazine (UDMH) (1,1-Dimethylhydrazine) is a hypergolic rocket fuel ingredient, often used as a bipropellant in combination with the oxidiser nitrogen tetroxide and less often with IRFNA or liquid oxygen. UDMH is a derivative of hydrazine and can be called a hydrazine too.
Untalkative Bunny Untalkative Bunny is a Canadian/Uk co-produced animated series about a yellow rabbit and its life in the big city (closely based on Ottawa, Canada.) The series consists of small episodes (about 4-5 minutes long each), and are aired by Teletoon, as well as Disney in many parts of the world including the UK & France.
Untamed Heart Untamed Heart is a 1993 film starring Christian Slater and Marisa Tomei. It mixes drama with romance and comedy and tells the story of a young woman, always unlucky in love, trying to find happiness with a very shy young man.
Unter den Linden Unter den Linden (in English: Under the Lindens), is a street in the centre of Berlin, the capital of Germany. It is named for its linden or lime trees which line the grassed pedestrian mall between the two carriageways.
Unterallgäu Unterallgäu is a Kreis (district) in the southwestern part of Bavaria, Germany. Neighboring districts are (from the north clockwise) Neu-Ulm, Günzburg, Augsburg, Ostallgäu, Oberallgäu, and the districts Ravensburg und Biberach in Baden-Württemberg.
Unterägeri Unterägeri is a municipality of the Canton of Zug, Switzerland, situated at the western shore of the Ägerisee. Known as Wilägeri, an outlying settlement of Ägeri, the community split in 1798, at the formation of the Helvetic Republic, into two municipalities, Oberägeri and Unterägeri.
Unterberger test The Unterberger test, also Unterberger's test and Unterberger's stepping test, is a test used in otolaryngology to help assess whether a patient has a vestibular pathology. It is not useful for detecting central (brain) disorders of balance.
Unterhaltungssoftware Selbstkontrolle Unterhaltungssoftware Selbstkontrolle (German Voluntary Monitoring Organisation of Entertainment Software) or USK, is Germany's software rating organisation. Since the modification of the Jugendschutzgesetz (Youth Protection Law) in 2003, it is now compulsory for all titles that are to be sold to the wider public to carry a USK mark.
Untermensch Untermensch (German for under man, sub-man, sub-human; plural: Untermenschen) is a term from Nazi racial ideology used to describe supposedly inferior people, especially "the masses from the East," that is Jews, Slavs, Gypsies, Soviet Bolshevists, and anyone else who was not a Nordic or Germanic Gentile.
Untermosel Untermosel is a Verbandsgemeinde ("collective municipality") in the district Mayen-Koblenz, in Rhineland-Palatinate, Germany. It is situated along the lower course of the Mosel, south-west of Koblenz.
Unteroffizier Unteroffizier is both a specific military rank as well as a collective term for non-commissioned officers of the German military that has existed since the 19th century. The rank existed as a title as early as the 17th century with the first wide spread usage occurring in the Bavarian Army of the 1800s.
Unteroffiziere mit Portepee Literally "Junior Officer with Swordknot", this is the designation for German senior non-commissioned officers in the German army. The name derives from earlier traditions in which senior enlisted men would carry a sword into battle.
Unteroffiziere ohne Portepee Literally "Non-commissioned officer without Swordknot", this is the designation for German junior non-commissioned officers (NCOs) in the German army. The name derives from earlier traditions in which German senior NCOs (Feldwebel) would carry the officer's sidearms (sword, sabre) with the officer's swordknot (made from silver or gold lace).
Unterseeboot 1 (1935) Unterseeboot 1 or U-1 was the first submarine (or U-boat) built for the Kriegsmarine following Adolf Hitler's repeal of the terms of the Treaty of Versailles in 1935, which banned Germany possessing a submarine force. The boat was built at the Deutsche Werke shipyards in Kiel, and her keel was laid on the 11 February 1935 amid celebration.
Unterseeboot 1000 Unterseeboot 1000 (usually abbreviated to U-1000) was a German submarine or U-boat, built during World War II for service in the Second Battle of the Atlantic. She was completed in Hamburg in November 1943, and after working up trials was moved to Egersund in Norway in June 1944.
Unterseeboot 1059 Unterseeboot 1059 (also known as U-1059) was a German World War II Type VIIF submarine commissioned on 1 May 1943. The U-1059 was one of four Type VIIF torpedo transport submarines, each could carry 39 torpedoes, and were used to re-supply other U-Boats at sea.
Unterseeboot 1060 U-1060 was a German World War II Type VIIF submarine commissioned on 15 May 1943. The U-1060 was one of four Type VIIF torpedo transport submarines; each could carry 39 torpedoes, and were used to re-supply other U-Boats at sea.
Unterseeboot 1061 U-1061 was a German World War II Type VIIF submarine commissioned on 25 August 1943. The U-1061 was one of four Type VIIF torpedo transport submarines; each could carry 39 torpedoes, and were used to re-supply other U-Boats at sea.
Unterseeboot 1062 Unterseeboot 1062 (also known as U-1062) was a German World War II Type VIIF submarine commissioned on 19 June 1943. The U-1062 was one of four Type VIIF torpedo transport submarines; each could carry 39 torpedoes, and were used to re-supply other U-Boats at sea.
Unterseeboot 107 Unterseeboot 107 or U-107 was one of the most successful Nazi German U-Boats to serve during World War II. Between January, 1941, and August, 1944, U-107 sailed on 16 active patrols at a time when a U-Boat would average a lifespan of 7 to 10 patrols.
Unterseeboot 110 Unterseeboot 110 (U-110) was a Type IXB submarine of the Kriegsmarine, captured by the Royal Navy on 9 May 1941, at which point a number of secret cipher documents were recovered. U-110's capture was later given the code word Operation Primrose and was one of the biggest secrets of the war.
Unterseeboot 1105 Unterseeboot-1105, a modified Type VII-C/41 German submarine, was built at the Nordseewerke Shipyard, Emden, Germany, and commissioned into the Kriegsmarine on 3 June 1944. Oberleutenant Hans-Joachim Schwarz was given command.
Unterseeboot 1226 Unterseeboot 1226 (usually abbreviated to U-1226) was a very short-lived German U-boat, built during World War II for service in the Second Battle of the Atlantic. The submarine was completed in Hamburg in November 1943, and placed under the command of Kptlt.
Unterseeboot 1234 Unterseeboot 1234 (usually abbreviated to U-1234) was an unusual German U-boat built during World War II for service in the Second Battle of the Atlantic. U-1234 was most notorous for having sunk twice, once by accident and once as part of the great destruction of the remaining German navy in the days before the surrender.
Unterseeboot 124 Unterseeboot 124 or U-124 was one of the most successful Nazi German U-Boats to serve in World War II. It was first launched on March 9th, 1940, with a crew of 54, under the command of Wilhelm Shultz up until September, 1941, when Johann Mohr took over command.
Unterseeboot 15 (1912) Unterseeboot 15 (also known as U-15) was one of the three Type U-13 class gasoline-powered U-boats produced by the German Kaiserliche Marine. On August 9, 1914, U-15 became the first U-boat loss to an enemy warship after it was rammed by British light cruiser HMS Birmingham.
Unterseeboot 175 Unterseeboot 175 was a German Type IXC U-Boat of the Kriegsmarine. Her keel was laid down on 30 January 1941 at the AG Weser shipyard of Bremen, and commissioned on 5 December 1941 with Kapitänleutnant Heinrich Bruns in command.
Unterseeboot 181 Unterseeboot 181 (U-181) was a Type IX U-boat, best known for her two patrols in 1942–43 under the command of Wolfgang Lüth. U-181 operated very successfully in the Indian ocean as well as South African waters.
Unterseeboot 183 Unterseeboot 183 (usually abbreviated to U-183) was a German submarine built during World War II. She was one of the so called "Monsun boats" or Monsun Gruppe, which operated in the Indian Ocean from Japanese bases in occupied Indonesia, mostly Penang.
Unterseeboot 192 Unterseeboot 192 (usually abbreviated to U-192) was a very short-lived German submarine built during World War II for service in the Second Battle of the Atlantic. During her maiden voyage in May 1943 she disappeared without a trace, along with her 55 crew.
Unterseeboot 193 Unterseeboot 193 (usually abbreviated to U-193) was a German submarine built during World War II for service in the Atlantic Ocean. She performed four war patrols in which she sank one ship, before being lost herself in the Bay of Biscay.
Unterseeboot 195 Unterseeboot 195 (U-195) was a German U-boat (submarine) used during World War II. It was one of two IX-D1 transport U-boats that had their forward torpedo tubes removed and the compartment converted to a cargo hold.
Unterseeboot 219 Unterseeboot 219 (U-219) was a German Type XB minelaying submarine (U-boat). This type of u-boat had a series of vertical flooded mineshafts ahead of the bridge along her centerline and a further bank of shafts either side of her conning tower.
Unterseeboot 22 (1936) Unterseeboot 22, or more commonly U-22 was a German submarine or U-boat which was commissioned in 1936 following construction as a Type IIB submarine at the Germaniawerft shipyards at Kiel. Her pre-war service was uneventful, as she trained crews and officers in the rapidly expanding U-boat arm of the Kriegsmarine following the abandonment of the terms of the Treaty of Versailles two years before.
Unterseeboot 227 Unterseeboot 227 (usually abbreviated to U-227) was a German Type IXC U-boat of the Kriegsmarine built for service in the Second Battle of the Atlantic, which was cursed with repeated bad luck during her brief service life. She was built during 1941 and 1942 by the Germaniawerft shipyards in the fleet base of Kiel, and was completed in August 1942, in prepaation for operations over the coming winter.
Unterseeboot 2321 Unterseeboot 2321, or more commonly U-2321 was the first of the highly advanced German Type XXIII submarines built for the Kriegsmarine in 1944 and 1945. As the first of this class, U-2321 was one of a handful of such boats to undertake an operational patrol, in March 1945.
Unterseeboot 2322 Unterseeboot 2322, or more commonly U-2322 was a highly advanced German Type XXIII submarine built for the Kriegsmarine in 1944. U-2322 was one of just a few such boats to undertake an operational patrol, and one of just three to undergo two.
Unterseeboot 2323 Unterseeboot 2323 (usually abbreviated to U-2323) was probably the shortest lived German U-boat during the whole of the Second World War. Constructed at Hamburg during the spring of 1944, she was a modern German Type XXIII submarine, completed on the 18 July and given to Kptlt.
Unterseeboot 2324 Unterseeboot 2324, or more commonly U-2324 was a highly advanced German submarine built for the Kriegsmarine in World War II. U-2324 was one of the last commissioned boats to undertake an operational patrol, and one of just three of her class to undergo two.
Unterseeboot 2331 Unterseeboot 2331 (usually abbreviated to U-2331) was a German Type XXIII submarine built during World War II intended for service against allied shipping in coastal waters. She was a brand new, high technology electric U-boat which was lost when only one month old in a bizarre training accident in the Baltic Sea.
Unterseeboot 234 Unterseeboot 234 (U-234) was a WWII German Type X submarine (U-boat), designed as a mine-layer, whose first and only mission into enemy territory consisted of the attempted delivery of uranium and other German advanced weapons technology to the Empire of Japan. The submarine surrendered to the United States after Germany's unconditional surrender on 9 May 1945.
Unterseeboot 2342 Unterseeboot 2342 (usually abbreviated to U-2342) was a short-lived German submarine during the Second World War. She was built at Hamburg during 1944 as a modern German Type XXIII submarine, a small coastal class designed to strike ships along the coastlines of Britain and liberated Europe, particularly the English Channel, although none ever served there.
Unterseeboot 238 Unterseeboot 238 (usually abbreviated to U-238) was a German Type VIIC submarine of the Kriegsmarine built for service in the Second World War. She was built during 1942 by Germaniawerft of Kiel, and she was commissioned February 20, 1943, with Oberleutnant zur See Horst Hepp in command.
Unterseeboot 2501 Unterseeboot 2501 (usually abbreviated to U-2501) was a German Type XXI submarine (an "Elektroboote") of the Kriegsmarine built for service in the Second World War. She was built during 1944 by Blohm & Voss of Hamburg, and she was commissioned on 27 June 1944 with Oberleutnant zur See Otto HĂĽbschen in command.
Unterseeboot 254 Unterseeboot 254 (usually abbreviated to U-254) was a German Type VIIC U-boat of the Kriegsmarine, built for service in the Second World War and the Second Battle of the Atlantic. She was a mildly successful boat on her three war patrols, but fell victim to a freak accident during an attack on an allied convoy in the mid-Atlantic Ocean on her third patrol and was lost.
Unterseeboot 28 (1913) The first Unterseeboot 28 (U-28) was a Type U-27 U-boat, ordered to be built on February 19, 1912, launched on August 30, 1913, from Kaiserliche Werft of Danzig, and commissioned into the Kaiserliche Marine on June 26, 1914 with Georg-GĂĽnther Freiherr von Forstner in command. Frhr.
Unterseeboot 303 Unterseeboot 303 (usually abbreviated to U-303) was a German U-boat built during World War II. She saw service in the Atlantic Ocean and Mediterranean Sea, and sank one frighter of 5,000 tons in her three short and uneventful war patrols.
Unterseeboot 309 Unterseeboot 309 (usually abbreviated to U-309) was a German U-boat built during World War II. She saw service in the Atlantic Ocean, and sank one frighter of 7,219 tons in her seven mostly uneventful war patrols.
Unterseeboot 346 Unterseeboot 346 or U-346 was an German submarine or U-boat, which was the victim of a tragic accident before it ever went to sea. The ship was a Type VIIC U-boat which was built in 1943 for operations during the Second Battle of the Atlantic during the Second World War.
Unterseeboot 3519 Unterseeboot 3519 (usually abbreviated to U-3519) was a German Type XXI submarine built during World War II intended for service in the Atlantic Ocean. She was a brand new, high technology electric boat which could run constantly submerged rather than having to surface to recharge her batteries every day the way submarines until that point had had to do.
Unterseeboot 36 (1936) Unterseeboot 36 (usually abbreviated to U-36) was a German Type VIIA submarine of the Kriegsmarine built for service in the Second World War. She was constructed in the earliest days of the U-boat arm of the Kriegsmarine at Kiel in 1936, and served in the pre-war Navy in the Baltic Sea and North Sea under her pre-war captain Klaus Ewert.
Unterseeboot 365 Unterseeboot 365 (usually abbreviated to U-365) was a German submarine built during World War II. She served exclusively against the Arctic Convoys from Britain to Murmansk and Archangelsk, principally targeting the Soviet forces which greeted the convoys in the Barents Sea.
Unterseeboot 388 Unterseeboot 388 was a Type VIIC U-boat, laid down on September 12, 1941 at Howaldtswerke, Kiel and commissioned on December 31, 1942. She conducted only one patrol from June 8 to June 20, 1943 and could not damage or sink any ship.
Unterseeboot 4 (1935) Unterseeboot 4 or U-4 was a submarine (or U-boat) of the Kriegsmarine during the Second World War. She was one of the longest lasting German submarines of the period, primarily since half of her lifepan was spent on training duties in the Baltic Sea.
Unterseeboot 470 Unterseeboot 470 (usually abbreviated to U-470) was a German Type VIIC submarine of the Kriegsmarine built for service in the Second Battle of the Atlantic during 1942. She was a very short-lived boat, being commissioned in the months following the turning point of the Atlantic campaign and thus into a time in which many U-boats were being lost.
Unterseeboot 48 (1939) The Unterseeboot 48, or U-48 was the most successful U-boat commissioned into the Kriegsmarine during the Second World War. During her two years of active service, U-48 sank 55 ships for 321,000 tons, and damaged two more at 12,000 tons on twelve war patrols conducted during the opening stages of the Second Battle of the Atlantic.
Unterseeboot 5 Unterseeboot 5 refers to five submarines of the German Navy. U 5 (Type U5), UB 5 (Type UB I), and UC 5 (Type UC I) all served in World War I, while U5 (Type IIA) served in World War II and U5 (type 205) in the cold war.
Unterseeboot 502 Unterseeboot 502 or U-502 was a very effective and successful Nazi German U-Boat that served during World War II. She was first launched on February 18th, 1941, with a crew of 52 under the command of Jurgen von Rosenstiel.
Unterseeboot 504 Unterseeboot 504 or U-504 was a Nazi German U-Boat that operated during World War II. It was first launched on April 24th, 1941, with a crew of 53 under the initial command of Hans-Georg Friedrich "Fritz" Poske.
Unterseeboot 505 Unterseeboot 505 is a Type IXC U-boat of the Kriegsmarine, notable for its capture by the United States Navy in 1944, and presently a museum ship at the Museum of Science and Industry in Chicago. Codebooks and other secret documents were captured from the U-505 which assisted Allied codebreaking operations.
Unterseeboot 507 Unterseeboot 507 (usually abbreviated to U-507) was a German Type IXC submarine of the Kriegsmarine built for service in the Second World War and the Second Battle of the Atlantic. U-507 was mainly notable for two patrols she conducted during the Second happy time in mid-1942, during the first of which she caused havoc in the Gulf of Mexico amongst unprotected American shipping, and then in the second attacked ships along the coast of Brazil, in an inexpliable and shocking attack on a neutral nation's shipping in its own waters which almost single- handedly provoked the Brazilian declaration of war on Germany.
Unterseeboot 509 Unterseeboot 509 (usually abbreviated to U-509) was a Type IXC U-Boat of Nazi Germany during World War II. Her keel was laid down on November 1 1940 at Deutsche Werft in Hamburg, and commissioned on November 4 1941.
Unterseeboot 51 Unterseeboot 51 or U-51 was a Nazi German U-Boat that operated with considerable shortlived success during World War II, between the dates of January 17th, 1940 and August 20th, 1940. It was first launched on June 11th, 1938, with a crew of 52 under the command of Dietrich Knorr.
Unterseeboot 512 Unterseeboot 512 (usually abbreviated to U-512) was a German Type IXC U-boat of the Kriegsmarine built for service in the Second Battle of the Atlantic. Although she was short lived, U-512 was a quite successful boat, making full use of the time she enjoyed in the entrance to the Caribbean Sea, during the Second happy time.
Unterseeboot 521 Unterseeboot 521, also known as U-521, was a German U-Boat commanded and commissioned by Kapitänleutnant Klaus Bargsten before being sunk on July 2, 1943 by PC-565. Strangely enough, the only survivor was Klaus Bargsten himself.
Unterseeboot 533 Unterseeboot 533 or U-533 was a Nazi German U-Boat that operated during World War II between April 15th, 1943, and October 16th, 1943. It was first launched on September 11th, 1942, with a crew of 53, under the command of Helmut Hennig.
Unterseeboot 550 The Unterseeboot 550 (U-550) was a Type IX C/40 U-boat. She was constructed by Deutsch Werft of Hamburg and was commissioned on 28 July 1943 under the command of Kapitänleutnant Klaus Hänert, (born 2 January 1918; Kriegsmarine Class of 1936).

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