Sunday, March 30, 2008

Primary storage

Primary storage, presently known as memory, is the only one directly reachable to the CPU. The CPU continuously reads commands stored there and executes them. Any data actively operate on is also stored there in uniform manner.

Historically, early computers used delay lines, Williams’s tubes, or revolving magnetic drums as primary storage. By 1954, those unreliable methods were frequently replaced by magnetic core memory, which was still rather cumbersome. Undoubtedly, a revolution was started with the invention of a transistor that soon enables then-unbelievable neatness of electronic memory via solid-state silicon chip technology.

This led to a modern random access memory (RAM). It is small-sized, light, but quite expensive at the same time. (The particular types of RAM used for primary storage are also volatile, i.e. loses the information when not powered).

Sunday, March 23, 2008

Carrot

The carrot (Daucus carota subsp. sativus) is a root vegetable, usually orange or white, or pink in color, with a crunchy texture when fresh. The suitable for eating part of a carrot is a taproot. It is a cultivated form of the wild carrot Daucus carota, national to Europe and southwestern Asia. It has been bred for its very much inflamed and more palatable, less woody-textured edible taproot, but is still the similar species.

It is a biennial plant which grows a rosette of leaves in the spring and summer, while building up the fat taproot, which stores big amounts of sugars for the plant to flower in the second year. The peak stem grows to about 1 m tall, with an umbel of white flowers.

Carrots can be eaten raw, whole, chopped, grate, or added to salads for color or texture. They are also often chopped and boiled, fried or steamed, and cooked in soups and stews, as well as fine baby foods and choose pet foods. A well recognized dish is carrots julienne. Grated carrots are used in carrot cakes, as healthy as carrot puddings, an old English dish thought to have originated in the early 1800s.

Sunday, March 16, 2008

Chocolate

Chocolate comprises a number of raw and process foods that are formed from the seed of the tropical cacao tree. Native to lowland tropical South America, cacao has been sophisticated for three millennia in Central America and Mexico, with its earliest recognized use about 1100 BC. All of the Mesoamerican peoples made chocolate beverages, as well as the Maya and Aztecs, who made it into a beverage known as xocolātl, a Nahuatl word meaning "bitter water". The seeds of the cacao tree have a controlling bitter taste, and must be fermented to develop the flavor. After being roasted and ground, the ensuing products are known as chocolate or cocoa.

Much of the chocolate inspired today is made into bars that combine with cocoa solids, fats like cocoa butter, and sugar. Chocolate has twist into one of the most popular flavors in the world. A chocolate lover is also called as "chocoholics." Gifts of frustrated wrapped chocolate molded into different shapes has become traditional on certain holidays: chocolate bunnies and eggs are popular on Easter, coins on Hanukkah, Santa Claus and further holiday symbols on Christmas, and hearts on Valentine's Day. Chocolate is also used in cold and hot beverages, to make chocolate milk and cocoa.

Sunday, March 09, 2008

Corporate bond

A corporate bond is a bond issued by a company; the term is usually applied to longer-term debt instruments, usually with a maturity date falling at least a year after their issue date. The term "commercial paper" is sometimes shabby for instruments with a shorter maturity.

Sometimes, the term "corporate bonds" is used to include all bonds separately from those issued by governments in their own currency. Strictly speaking, however, it only applies to those issued by corporations.

Monday, March 03, 2008

Mercury

Mercury (pronounced /'m?kj??ri/) is the deepest and smallest planet in the solar system, orbiting the Sun once every 88 days. Mercury is bright when viewed from Earth, range from -2.0 to 5.5 in apparent magnitude, but is not easily seen as its greatest angular separation from the Sun (greatest elongation) is only 28.3°: It can only be seen in morning and evening twilight. Comparatively little is known about it; the first of two spacecraft to move toward Mercury was Mariner 10 from 1974 to 1975, which mapped only about 45% of the planet’s surface. The second was the MESSENGER spacecraft, which mapped another 30% of the planet throughout its flyby of January 14, 2008. MESSENGER will make two more passes by Mercury, follow by orbital insertion in 2011, and will survey and map the whole planet.