Saturday, December 29, 2007

Pets

A pet is an animal kept for companionship and enjoyment, as opposed to livestock, laboratory animals, working animals or sport animals, which are kept for economic reasons. The most popular pets are noted for their loyal or playful characteristics, for their attractive appearance, or for their song. Pets also generally seem to provide their owners with non-trivial health benefits; keeping pets has been shown to help relieve stress. There is now a medically-approved class of therapy animals, mostly dogs, who are brought to visit confined humans. Walking a dog can provide both the owner and the dog with exercise, fresh air, and social interaction.

Koko the gorilla is one of few examples of a non-human animal which has had an explicit pet. Using sign language, she requested a cat; her first pet was a kitten named All Ball, to which she was reported to be quite attached and mourned for several days after the cat escaped and was killed by a car.

The GloFish is a genetically modified fluorescent zebrafish with bright red, green, and orange fluorescent color. It is the first genetically modified animal to become available as a pet.

Wednesday, December 19, 2007

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.

Thursday, December 13, 2007

Computers

Computers take numerous physical forms. The first devices that resemble modern computers date to the mid-20th century, although the computer concept and various machines similar to computers existed prior. Early electronic computers were the size of a large room, consuming as much power as several hundred modern personal computers. Modern computers are based on comparatively 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 wrist watch 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 by far the embedded computer. Embedded computers are small, simple devices that are often used to control other devices-for example, they may be found in machines ranging from fighter aircraft to industrial robots, digital cameras, and even 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 mathematical 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 capability 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