half-disk
51Portal (video game) — Portal Portal s box art displays a figure moving into a portal. Signs of this style are commonly used in the game s environment. Developer(s) …
52Differential geometry of surfaces — Carl Friedrich Gauss in 1828 In mathematics, the differential geometry of surfaces deals with smooth surfaces with various additional structures, most often, a Riemannian metric. Surfaces have been extensively studied from various perspectives:… …
53arts, East Asian — Introduction music and visual and performing arts of China, Korea, and Japan. The literatures of these countries are covered in the articles Chinese literature, Korean literature, and Japanese literature. Some studies of East Asia… …
54Planet — This article is about the astronomical object. For other uses, see Planet (disambiguation) …
55Battery (electricity) — For other uses, see Battery (disambiguation). Various cells and batteries (top left to bottom right): two AA, one D, one handheld ham radio battery, two 9 volt (PP3), two AAA, one C, one …
56computer — computerlike, adj. /keuhm pyooh teuhr/, n. 1. Also called processor. an electronic device designed to accept data, perform prescribed mathematical and logical operations at high speed, and display the results of these operations. Cf. analog… …
57metalwork — metalworker, n. /met l werrk /, n. objects made of metal. [1840 50; METAL + WORK] * * * Useful and decorative objects fashioned of various metals. The oldest technique is hammering. After с 2500 BC, casting was also used, molten metal being… …
58pregnancy — /preg neuhn see/, n., pl. pregnancies. the state, condition, or quality of being pregnant. [1520 30; PREGN(ANT) + ANCY] * * * Process of human gestation that takes place in the female s body as a fetus develops, from fertilization to birth (see… …
59Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …
60Extraterrestrial skies — The sky of a world refers to the view of the heavens from its surface. This view varies from world to world for many reasons. The most important factor in the appearance of a world s sky is its atmosphere, or the lack thereof. Depending on the… …
