Computer Printer

A computer printer, or more commonly a printer, produces a hard copy of documents stored in electronic form, usually on substantial print media such as paper or transparencies. Many printers are principally used as local computer peripherals, and are attached by a printer cable to a computer which serves as a document resource. Some printers, commonly known as network printers, have built-in network interfaces, and can serve as a hardcopy device for any user on the network. Individual printers are often designed to support both local and network connected users at the same time.

In addition, many modern printers can directly interface to electronic media such as memory sticks or memory cards, or to image detain devices such as digital cameras, scanners; some printers are combined with a scanners and/or fax machines in a single unit. Printers that include non-printing features are sometimes called Multi-Function Printers (MFP) or Multi-Function Devices (MFD).

A printer which is combined with a scanner can function as a photocopier if so designed. Most MFPs include printing, scanning, and copying among their features. Printers are designed for low-volume, short-turnaround print jobs; requiring practically no setup time to achieve a hard copy of a given document. However, printers are generally slow devices (30 pages per minute is considered fast; and many consumer printers are far slower than that), and the cost-per-page is relatively high.

In contrast, the printing press (which serves much the same function), is designed and optimized for high-volume print jobs such as newspaper print runs--printing presses are capable of hundreds of pages per minute or more, and have an incremental cost-per-page which is a portion of that of printers. The printing press remains the machine of choice for high-volume, proficient publishing. However, as printers have improved in quality and performance, many jobs which used to be done by proficient print shops are now done by users on local printers; see desktop publishing. The world's first computer printer was a 19th century involuntarily driven apparatus invented by Charles Babbage for his Difference Engine.

Computer

A computer is a machine that manipulates data according to a list of instructions.
Computers take plentiful physical forms. The first devices that be similar to modern computers date to the mid-20th century (around 1940 - 1945), although the computer concept and various machines similar to computers existed earlier. Early electronic computers were the size of a large room, strong as much power as several hundred modern personal computers. Modern computers are based on relatively tiny integrated circuits and are millions to billions of times more capable while occupying a fraction of the space.

Today, simple computers may be made small enough to fit into a wristwatch and be powered from a watch battery. Personal computers in various forms are icons of the Information Age and are what most people think of as "a computer"; however, the most common form of computer in use today is the surrounded computer. Embedded computers are small, simple devices that are used to control other devices, for example, they may be found in machines ranging from fighter aircraft to industrial robots, digital cameras, and children's toys.

The ability to store and execute lists of instructions called programs makes computers extremely versatile and distinguishes them from calculators. The Church–Turing thesis is a arithmetical statement of this versatility: any computer with a certain minimum capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore, computers with potential and complexity ranging from that of a personal digital assistant to a supercomputer are all able to perform the same computational tasks given enough time and storage capacity.

Birds

Many species of bird undertake long distance annual migrations, and many more perform shorter irregular movements. Birds are social and communicate using visual signals and through calls and song, and participate in social behaviors including cooperative hunting, cooperative breeding, flocking and mobbing of predators. Birds are primarily socially monogamous, with engagement in extra-pair copulations being common in some species-other species have polygamous or polyandrous breeding systems. Eggs are regularly laid in a nest and incubated and most birds have an extended period of parental care after hatching.

Birds are economically important to humans: many are important sources of food, acquired either through hunting or farming, and they provide other products. Some species, particularly songbirds and parrots, are popular as pets. Birds figure prominently in all aspects of human culture from religion to poetry and popular music. About 120-130 species have become extinct as a result of human activity since 1600, and hundreds more before this. Currently around 1,200 species of birds are threatened with extinction by human activities and efforts are underway to protect them.

Tsunami

A tsunami is a series of waves shaped when a body of water, such as an ocean, is rapidly displaced. Earthquakes, group movements above or below water, volcanic eruptions and other underwater explosions, landslides, large meteorite impacts and testing with nuclear weapons at sea all have the potential to produce a tsunami. The effects of a tsunami can range from imperceptible to devastating. The word tsunami comes from the Japanese words meaning harbor and wave. For the plural, one can either follow usual English practice and add an s, or use an invariable plural as in Japanese. The term was created by fishermen who returned to port to find the area neighboring their harbor devastated, although they had not been conscious of any wave in the open water. Tsunamis are general throughout Japanese history; approximately 195 events in Japan have been recorded.

A tsunami has a much smaller amplitude (wave height) offshore, and a very long wavelength, which is why they generally pass unobserved at sea, forming only a passing bulge in the ocean. Tsunami have been historically referred to as tidal waves because as they approach land, they take on the characteristics of a vicious onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean. Since they are not really related to tides the term is considered misleading and its treatment is discouraged by oceanographers.

Resistance

Electrical resistance is a compute of the degree to which an object opposes an electric current through it. The SI unit of electrical resistance is the ohm. Its reciprocal quantity is electrical conductance calculated in siemens. Electrical resistance shares some conceptual parallels with the mechanical notion of friction.

The resistance of an object determines the amount of current through the object for a known voltage across the object I=V/R, where R is the resistance of the object, measured in ohms, equivalent to J•s/C2, V is the voltage across the object, measured in volts, I is the current through the object, measured in amperes. In metals, the Fermi level lies in the conduction band giving rise to free transfer electrons. However, in semiconductors the position of the fermi level is within the band gap, closely half way between the conduction band minimum and valence band maximum for intrinsic semiconductors.

space shuttle

NASA's Space Shuttle, officially called Space Transportation System (STS), is the United States government's present manned launch vehicle. At launch, it consists of a rust-colored outer tank, two white, slender solid rocket boosters (SRBs), and a winged orbiter. The orbiter carries astronauts and payload such as satellites or space location parts into low earth orbit. Normally, five to seven astronauts ride in the orbiter, with two pilots, eight have been carried, and eleven could be accommodated in an urgent situation landing.

When the orbiter's work is complete, it fires its orbital maneuvering thrusters to drop out of orbit and re-enters the Earth's atmosphere. During the descent and landing, the shuttle orbiter acts as a glider and makes a completely unpowered landing. Five spaceworthy orbiters were build, of which three remain.

The Shuttle is the first orbital spacecraft considered for partial reusability. It carries large payloads to various orbits, provides crew rotary motion for the International Space Station (ISS), and performs servicing missions. The orbiter can also recover satellites and other payloads from orbit and return them to Earth, but this capability has not been used often. However, it has been used to return large payloads from the ISS to Earth, as the Russian Soyuz spacecraft has limited capacity for return payloads. Each Shuttle was designed for a expected lifespan of 100 launches or 10 years' operational life.

Entertainment

Entertainment is an occasion, piece, or movement designed to give enjoyment or leisure to an audience. The audience may join in the entertainment passively as in actively as in computer games. The playing of sports and reading of journalism are usually included in entertainment, but these are regularly called activity more specifically, because they involve some energetic participation past mere leisure.

While people have laughing themselves since the beginning of time, the entertainment industry first became a leading force in culture in the 20th century with the development of latest electronic technologies of recording and spreading. Western peoples, tired of serious purposes and gathering massacre, turned to popular culture following the two world wars. The financial basis of this new culture was advertising of free or inexpensive entertainment program. In their peak, television networks were great selling machines which, besides entertaining people, prohibited both commercial and political markets by providing direct access to the group of customers. This "territory" is now in danger by the explosion and segmentation of media and especially by the growing importance of communication by computer which allows the consumer to look for out the informational message as an alternative of having it broadcast to him or her. A new system of world history sees Americans in changeover between a fourth, entertainment-based "society" and a future fifth evolution based on computer communication.

Blue tooth

Blue tooth is an industrial requirement for wireless personal area networks.Blue tooth provides a way to connect and swap information between devices such as mobile phones, laptops, PCs, printers, digital cameras, and video game consoles over a secure, globally unlicensed short-range radio frequency. The Blue tooth specifications are licensed and developed by the Blue tooth Special Interest Group.

Blue tooth is a radio standard and communications protocol mostly designed for low power consumption, with a short range based on low-cost transceiver microchips in each device. The devices use a radio communications system, so they do not have to be in line of view of each other, and can even be in other rooms, as long as the conservative transmission is powerful enough.

Hockey

Hockey is any of a family of sports in which two teams struggle by trying to maneuver a ball, or a hard, surrounding disc called a puck, into the opponent's net or goal, using a hockey stick. Field hockey is played on nettle, natural grass, sand-based or water-based artificial turfs, with a small, hard ball. The game is popular among both males and females in many countries of the world, mostly in Europe, India, Pakistan, Australia, New Zealand, South Africa and South Asia. In most countries, the game is played between single-sex sides, even though it can be played by mixed-sex sides. In the United States and Canada it is played mostly by women. Ball hockey is played in a gym using sticks and a ball, often a tennis ball with the hair removed.

There are early representations and reports of hockey-type games being played on ice in the Netherlands, and reports from Canada from the beginning of the nineteenth century, but the modern game was initially planned by students at McGill University, Montreal in 1875 who, by two years later, codified the first set of ice hockey rules and organized the first teams.

Race

The term race describes populations or groups of people well-known by different sets of characteristics, and beliefs about common ancestry. The most broadly used human racial categories are based on visible traits, and self-identification. Conceptions of race, as well as specific ways of grouping races, vary by culture and over time, and are often contentious for scientific as well as social and political reasons. Many scientists contend that while the features on which a racial categorization are made may be based on genetic factors, the idea of race itself, and actual divisions of persons into groups based on selected hereditary features, are social constructs.
Since the 1940s, some evolutionary scientists have rejected the view of race as a biologically meaningful impression. A majority of evolutionary scientists reject the notion that any definition of race pertaining to humans can have any taxonomic rigour and validity. Mainstream scientists have argued that race definition are imprecise, arbitrary, derived from custom, have many exceptions, have many gradations, and that the numbers of races experimental vary according to the culture examined. They further preserve that race as such is best understood as a social construct.

Security

Security is the condition of being sheltered against danger or loss. In the general sense, security is a perception similar to safety. The nuance between the two is an added emphasis on being protected from dangers that initiate from outside. Individuals or actions that encroach upon the condition of protection are responsible for the breach of security.
The word security in general procedure is synonymous with safety, but as a technical term security means that something not only is protected but that it has been secured. A condition that results from the establishment and maintenance of protective measures that ensures a state of inviolability from hostile acts or influences. With respect to classified matter, the condition that prevents unauthorized persons from having right to use to official information that is safeguarded in the benefit of national security.

Planet

A planet, as defined by the International Astronomical Union (IAU), is a celestial body orbiting a star or stellar remains that is massive enough to be rounded by its own gravity, not massive enough to cause thermonuclear fusion in its core, and has cleared its neighboring region of planetesimals. The term planet changed from something that stimulated across the sky, to a body that orbited the Earth. When the heliocentric model gained sway in the 16th century, it became established that a planet was actually something that directly orbited the Sun. At the end of the 17th century, when the first satellites of Saturn were exposed, the terms planet and satellite were at first used interchangeably, although satellite would gradually become more common in the following century.

The energetic impacts of the smaller planetesimals will heat up the increasing planet, causing it to at least partially melt. The interior of the planet begins to differentiate by mass, mounting a denser core. Smaller terrestrial planets lose most of their atmospheres because of this accretion, but the lost gases can be replaced by out gassing from the mantle and from the succeeding impact of comets.

Earthquake

An earthquake is the result of a sudden release of stored energy in the Earth's outer layer that creates seismic waves. Earthquakes are accordingly measured with a seismometer, generally known as a seismograph. The magnitude of an earthquake is conventionally reported using the Richter scale or a related instant scale. At the Earth's surface, earthquakes may manifest themselves by a trembling or displacement of the ground. Sometimes, they cause tsunamis, which may lead to loss of life and annihilation of property. An earthquake is caused by tectonic plates getting stuck and putting a damage on the ground. The strain becomes so great that rocks give way by breaking and downhill along fault planes. Earthquakes may occur naturally or as a result of human actions. Slighter earthquakes can also be caused by volcanic activity, landslides, mine blasts, and nuclear tests. In its most generic intelligence, the word earthquake is used to describe any seismic event—whether a natural phenomenon or an event caused by humans—that generates seismic effect.

Cloud

A cloud is a visible mass of condensed droplets, frozen crystals suspended in the atmosphere above the surface of the Earth or another earthly body, such as a moon. The branch of meteorology in which exhaust are studied is nephology.
On Earth the condensing matter is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm in diameter. When surrounded by billions of other droplets or crystals they become observable as clouds. Dense deep clouds exhibit a high reflectance throughout the visible range of wavelengths: they thus appear white, at least from the top. Cloud droplets tend to scatter light professionally, so that the intensity of the solar radiation decreases with depth into the cloud, hence the gray or even sometimes dark exterior of the clouds at their base. Thin clouds may appear to have acquired the color of their environment or background, and clouds illuminated by non-white light, such as through sunrise or sunset, may be colored accordingly. In the near-infrared range, clouds would appear darker because the water that constitutes the cloud droplets muscularly absorbs solar radiation at those wavelengths.

Inca Rope bridge

Inca Rope bridges were simple suspension bridges over canyons and gorges to present access for the Inca Empire. Bridges of this type were suitable for use since the Inca people did not use wheeled transport - traffic was incomplete to pedestrians and livestock. These bridges were an intrinsic part on the Inca road scheme and are an excellent example of Inca innovation in engineering. They were frequently used by Chasqui runners delivering messages throughout the Inca Empire.
The construction of these bridges amounted to a pair of stone anchors on each side of the canyon with immense cables of woven ichu grass linking these two pylons together. Adding to this construction, two additional cables acted as guardrails. The cables which supported the foot-path were unbreakable with plaited branches. This multi-structure system made these bridges strong enough to even carry the Spaniards while riding horses after they indoors. However, these massive bridges were so heavy that they tended to sag in the middle, and this caused them to bend in high winds.

Calculator

A calculator is a machine for performing calculations. Although modern calculators often incorporate a general purpose computer, the device is calculated for performing specific operations, rather than for flexibility. Modern calculators are more convenient than most computers, though some PDAs are comparable in amount to handheld calculators.

In the past, some calculators were as huge as today's computers. The first automatic calculators were mechanical desktop devices which were replaced by electromechanical desktop calculators, and then by electronic devices using first thermionic valves, then transistors, then hard-wired integrated circuit logic. New calculators are electrically powered and come in innumerable shapes and sizes varying from cheap, give-away, credit-card sized models to more sturdy adding machine-like models with built-in printers.

Indicator

Dial indicators are instruments used to correctly measure a small distance. They may also be known as a Dial gauge, Dial Test Indicator, or as a clock. They are named so because the measurement results are displayed in a overstated way by means of a dial. They may be used to check the dissimilarity in tolerance during the check process of a machined part, measure the deflection of a beam or ring under laboratory conditions, as well as many other situations where a small measurement needs to be registered or indicated.

An economic indicator is a statistic concerning the economy. The lighting system of a motor vehicle consists of lighting and signaling procedure mounted or integrated to the front, sides and rear of the vehicle. The purpose of this system is to present illumination for the driver to operate the vehicle safely after dark, to increase the visibility of the vehicle, and to display information about the vehicle's presence, position, size, direction of travel, and driver's intentions concerning direction and speed of travel.

Reliability

In computer networking, a reliable protocol is one that ensures that reliability properties with respect to the delivery of data to the intended recipient(s), as opposed to an unreliable procedure, which does not guarantee that data will be delivered intact, or that it will be delivered at all. A reliable multicast protocol may ensure consistency on a per-recipient basis, as well as provide strong reliability properties that relate the delivery of data to different recipients, such as e.g. total order, atomicity, or virtual synchrony.

Reliable protocols normally incur more overhead than unreliable protocols, and as a result, are slower and less scalable. This often isn't an issue for unicast protocols, but it may be a difficulty for multicast protocols. TCP, the main protocol used in the Internet today, is a reliable unicast protocol. UDP, often used in computer games or other situation where speed is an issue and the loss of a little fact is not, is an unreliable unicast protocol.

Table

In relational databases, SQL databases, and flat file databases, a table is a set of data elements that is controlled using a model of horizontal rows and vertical columns. The columns are identified by name, and the rows are identified by the values appearing in a particular column division which has been identified as a candidate key. Table is another term for family although there is the difference in that a table is usually a multi-set of rows whereas a relation is a set and does not allow duplicates. A table has a particular number of columns but can have any number of rows. Besides the actual data rows, tables generally have related with them some meta-information, such as constraints on the table or on the values within particular columns.

The data in a table does not have to be actually stored in the database. Views are also relational tables, but their data is considered at query time. In non-relational systems, such as hierarchical databases, the isolated counterpart of a table is a structured file, representing the rows of a table in each record of the file and each column in a record.

Trams

Electric-powered trams were first successfully experienced in service in Richmond, Virginia, in 1888, in the Richmond Union Passenger Railway built by Frank J. Sprague. There were earlier saleable installations of electric streetcars, including one in Berlin, as early as 1881 by Werner von Siemens and the company that still bears his name, and also one in Saint Petersburg, Russia, made-up and tested by Fyodor Pirotsky in 1880. Another was by John Joseph Wright, brother of the celebrated mining entrepreneur Whitaker Wright, in Toronto in 1883.The earlier installations, however, proved difficult and/or variable. Siemens' line, for example, provided power through a live rail and a return rail, like a model train setup, limiting the voltage that could be used, and providing unwanted stimulation to people and animals crossing the tracks. Siemens later planned his own method of current collection, this time from an overhead wire, called the bow collector. Once this had been developed his cars became equal to, if not superior than, any of Sprague's cars. The first electric interurban line connecting St. Catherine’s and Thorold, Ontario was operated in 1887, and was measured quite successful at the time. While this line proved quite versatile as one of the earliest fully functional electric streetcar installations, it still required horse-drawn carry while hiking the Niagara Escarpment and for two months of the winter when hydroelectricity was not available. This line continuous service in its original form well into the 1950s.