Sunday, May 27, 2007
Boat
A boat is a watercraft intended to float on, and offer transport over, water. Usually this water will be inland or in protected coastal areas. However, boats such as the whaleboat were historically intended to be operated from a ship in an offshore environment. In Naval terms, a boat is something small enough to be carried aboard another vessel (a ship). Boats that are notable exceptions to this concept due to their huge size are the Great Lakes freighter, riverboat, and ferryboat. These examples do, however, usually operate on inland and protected coastal waters. Modern submarines may also be referred to as boats (in spite of underwater capabilities and size), but this is perhaps due to the fact that the first submarines could be carried by a ship and were certainly not capable of making offshore passages on their own. Boats may have military, other government, research, or commercial usage; but a vessel, regardless of size, that is in private, non-commercial usage is almost definitely a boat.
Sunday, May 20, 2007
Metal
In chemistry, a metal is an constituent that readily loses electrons to form positive ions and has metallic bonds between metal atoms. Metals form ionic bonds with non-metals. They are sometimes described as a web of positive ions surrounded by a cloud of delocalized electrons. The metals are one of the three groups of elements as eminent by their ionization and bonding properties, along with the metalloids and nonmetals. On the periodic table, a diagonal line drawn from boron separates the metals from the nonmetals. Most elements on this line are metalloids, sometimes called semi-metals; elements to the lower left are metals; elements to the upper right are nonmetals.
A modern definition of metals is that they have overlapping conveyance bands and valence bands in their electronic structure. This definition opens up the category for metallic polymers and other organic metals, which have been prepared by researchers and employed in high-tech devices. These synthetic materials often have the characteristic silvery-grey reflectiveness of elemental metals.
A modern definition of metals is that they have overlapping conveyance bands and valence bands in their electronic structure. This definition opens up the category for metallic polymers and other organic metals, which have been prepared by researchers and employed in high-tech devices. These synthetic materials often have the characteristic silvery-grey reflectiveness of elemental metals.
Sunday, May 13, 2007
Geography
Geography is the study of the earth and its features and of the circulation of life on the Earth. A literal transformation would be "to describe the Earth". The first person to use the word "geography" was Eratosthenes (275-195 B.C.). Four historical civilization in geographical research are the spatial analysis of natural and human phenomena, area studies, study of man-land relationship, and investigate in earth sciences. Nonetheless, modern geography is an all-inclusive discipline that foremost seeks to understand the world and all of its human and natural complexities-- not merely where things are, but how they have changed and come to be. It is said to be the "mother of all math" and "the synthesizer of information." Geography is mainly divided into two main branches - human geography and physical geography.
conventionally, geography as well as geographers has been viewed as the same as cartography and people who study place names. Although many geographers are capable in toponymy and cartography, this is not their main preoccupation. Geographers study the spatial and temporal allotment of phenomena, processes and feature as well as the interaction of humans and their environment. As space and place persuade a variety of topics such as economics, health, climate, plants and animals, geography is highly interdisciplinary.
conventionally, geography as well as geographers has been viewed as the same as cartography and people who study place names. Although many geographers are capable in toponymy and cartography, this is not their main preoccupation. Geographers study the spatial and temporal allotment of phenomena, processes and feature as well as the interaction of humans and their environment. As space and place persuade a variety of topics such as economics, health, climate, plants and animals, geography is highly interdisciplinary.
Sunday, May 06, 2007
CD-ROM
CD-ROM (an abbreviation of "Compact Disc read-only memory") is a Compact Disc that contains information accessible by a computer. While the Compact Disc format was formerly designed for music storage and playback, the format was later adapted to hold any form of binary data. CD-ROMs are commonly used to distribute computer software, including games and multimedia applications, though any data can be stored (up to the capacity limit of a disc). Some CDs seize both computer data and audio with the latter capable of being played on a CD player, whilst data (such as software or digital video) is only usable on a computer. These are called Enhanced CDs.
Although many people use lowercase letters in this acronym, proper appearance is in all capital letters with a hyphen between CD and ROM. It was also suggested by some, specially soon after the technology was first released, that CD-ROM was an acronym for "Compact Disc read-only-media", or that it was a more 'correct' definition. This was not the purpose of the original team who developed the CD-ROM, and common acceptance of the 'memory' definition is now almost universal. This is probably in no small part due to the prevalent use of other 'ROM' acronyms such as Flash-ROMs and EEPROMs where 'memory' is the correct term.
Although many people use lowercase letters in this acronym, proper appearance is in all capital letters with a hyphen between CD and ROM. It was also suggested by some, specially soon after the technology was first released, that CD-ROM was an acronym for "Compact Disc read-only-media", or that it was a more 'correct' definition. This was not the purpose of the original team who developed the CD-ROM, and common acceptance of the 'memory' definition is now almost universal. This is probably in no small part due to the prevalent use of other 'ROM' acronyms such as Flash-ROMs and EEPROMs where 'memory' is the correct term.
