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digital versatile disc

(Encyclopedia)digital versatile disc or digital video disc (DVD), a small plastic disc used for the storage of digital data. The successor media to the compact disc (CD), a DVD can have more than 100 times the stor...

fault

(Encyclopedia)CE5 Types of faults fault, in geology, fracture in the earth's crust in which the rock on one side of the fracture has measurable movement in relation to the rock on the other side. Faults on othe...

fireproofing

(Encyclopedia)fireproofing, method of making normally combustible materials as nearly noncombustible as possible. Fireproofing generally applies to textiles and construction materials that are treated with a soluti...

Roman roads

(Encyclopedia)Roman roads, ancient system of highways linking Rome with its provinces. Their primary purpose was military, but they also were of great commercial importance and brought the distant provinces in touc...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

data encryption

(Encyclopedia)data encryption, the process of scrambling stored or transmitted information so that it is unintelligible until it is unscrambled by the intended recipient. Historically, data encryption has been used...

potato

(Encyclopedia)potato or white potato, common name for a perennial plant (Solanum tuberosum) of the family Solanaceae (nightshade family) and for its swollen underground stem, a tuber, which is one of the most widel...

plate tectonics

(Encyclopedia)CE5 Plate tectonics: Map of the world showing major plates and plate boundaries CE5 Plate tectonics: Schematic model of the oceanic crust, showing the three types of plate boundaries plate tect...

Platyhelminthes

(Encyclopedia)CE5 A. Planaria, representative of the phylum Platyhelminthes B. Internal anatomy of Planaria Platyhelminthes plătˌēhĕlmĭnˈthēz [key], phylum containing about 20,000 species of soft-bodied,...

Tertiary period

(Encyclopedia)Tertiary period tûrˈshēĕrˌē [key], name for the major portion of the Cenozoic era, the most recent of the geologic eras (see Geologic Timescale, tablegeologic timescale, table) from around 26 to...