Pragmatism is a philosophical tradition that began in the United States around 1870. Pragmatism is a rejection of the idea that the function of thought is to describe, represent, or mirror reality. Instead, pragmatists develop their philosophy around the idea that the function of thought is as a instrument or tool for prediction, action, and problem solving. Pragmatists contend that most philosophical topics - such as the nature of knowledge, language, concepts, meaning, belief, and science - are all best viewed in terms of their practical uses and successes rather than in terms of representative accuracy.

The Vikings were seafaring north Germanic people who raided, traded, explored, and settled in wide areas of Europe, Asia, and the North Atlantic islands from the late 8th to the mid-11th centuries. The Vikings employed wooden longships with wide, shallow-draft hulls, allowing navigation in rough seas or in shallow river waters. The ships could be landed on beaches, and their light weight enabled them to be hauled over portages. These versatile ships allowed the Vikings to travel as far east as Constantinople and the Volga River in Russia, as far west as Iceland, Greenland, and Newfoundland, and as far south as Nekor. This period of Viking expansion, known as the Viking Age, constitutes an important element of the medieval history of Scandinavia, Great Britain, Ireland, Russia, and the rest of Europe.

The South Shore Estuary is an estuary located along the south shore of Long Island, between the mainland and the outer barrier islands, in eastern New York state. It stretches for over 70 miles (110 km) from West Bay in Nassau County to the Shinnecock Bay in Suffolk County.

The Doppler effect (or Doppler shift), named after the Austrian physicist Christian Doppler, who proposed it in 1842 in Prague, is the change in frequency of a wave (or other periodic event) for an observer moving relative to its source. It is commonly heard when a vehicle sounding a siren or horn approaches, passes, and recedes from an observer. The received frequency is higher (compared to the emitted frequency) during the approach, it is identical at the instant of passing by, and it is lower during the recession.

Speed skating is a competitive form of ice skating in which the competitors race each other in traveling a certain distance on skates. Types of speed skating are long track speed skating, short track speed skating, and marathon speed skating. Short track speed skating takes place on a smaller rink, normally the size of an ice hockey rink. Distances are shorter than in long track racing, with the longest Olympic race being 3000 meters. Races are usually held as knockouts, with the best two in heats of four or five qualifying for the final race, where medals are awarded. Disqualifications and falls are not uncommon. The sport originates from pack-style events held in North America and was officially sanctioned in the 1970s, becoming an Olympic sport in 1992. Although this form of speed skating is newer, it is growing faster than long track speed skating, largely because short track can be done on an ice hockey rink rather than a long-track oval.