 | | Advantages of External Hard DriveAn external hard drive has become indispensable because there are potential security threats to our computers like virus due to Internet access even after employing anti-virus programs and firewalls.
Apart from this, inadvertent corruption of sensitive documents and additional space required for multimedia storage are some of the problems and one single solution to all such problems is the external hard drive.
The external hard drive is enclosed in an enclosure outside the main computer and is slightly larger than the hard drive itself and sometimes has a cooling fan. The external hard drive is connected to the computer through a high-speed interface cable, which enables the external hard drive to communicate with the computer by means of interfaces like USB and Fire Wire.
An external hard drive is a very constructive piece of equipment in the sense that it allows the user to back up or store important information detached from the main internal hard drive, which could be affected by on-line or off-line activities. An external hard drive can hold sensitive documents, DVD images, disc images, large music files, movies and also a back up of the contents of the main internal hard drive safely and securely. When on line, external hard drive can even be left turned off.
An external hard drive has another advantage it is portable and operates on plug and play basis. The external hard drive can be used as a storage device for any computer with a USB or Fire Wire capability.
Hard drives are available in two basic formats: SATA (Serial Advanced Technology Attachment) and IDE (Integrated Drive Electronics). IDE drives use a 40-pin connection and are cheaper and SATA hard drives are faster and transfer data at six times the speed of IDE external hard drive.
An external hard drive is basically composed of the Platters, the Spindles and Spindle Motor, the Read/Write Head and the Head Actuator.
The Platters are the actual discs inside the external drive that store the magnetized data. Platters made of glass or ceramic are used because they are thinner and are more heat resistant. Generally, the external hard drives have at least two platters and the larger the storage capacity of the hard drive the more the platters. The Spindle Motor is built right into the Spindle and spins the Platter at a constant set rate ranging from 3600 to 7200 rpm. The Read/Write Head reads and writes the data to the Platter. There is necessarily one head per platter side and each head is attached to a single actuator shaft. Only one of the heads is active at a time reading or writing the data. All the heads are attached to a single head actuator, which moves the head around the Platters. The platters spindle, spindle motor, head actuator and the read or write head are all contained in a chamber called the Hard Disc Assembly (HDA)
We can even buy several hard drives and barter them in and out of the same enclosures, using one for work, one for back up, and one for multi media and song and so on and thus there are boundless reasons to use an external hard drive. |
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| The Hundred-Year Lie: How to Protect Yourself from the Chemicals That Are Destroying Your Health
by Randall Fitzgerald |  | In the tradition of Silent Spring and Fast Food Nation, investigative journalist Randall Fitzgerald warns how thousands of man-made chemicals in our food, water, medicine, and environment are making humans the most polluted species on the planet. A century ago in 1906, when Congress enacted the Pure Food and Drug Act, Americans were promised "better living through chemistry." Fitzgerald provides overwhelming evidence to shatter this myth, and many others perpetrated by the chemical, pharmaceutical, and processed foods industries.
Plume (June 26, 2007)
Product Dimensions: 8.4 x 5.2 x 0.7 inches
Paperback: 304 pages | Consider This:- The average American carries a "body burden" of 700 synthetic chemicals
- Chemicals in tap water can cause reproductive abnormalities and hermaphroditic birth
- A 2005 study of lactating women in eighteen U.S. states found perchlorate (a toxic component of rocket fuel) in practically every mother's breast milk
- Lab tests have found that four common food additives-aspartame, MSG, and two coloring chemicals-interact synergistically to produce nerve damage. These additives are commonly found in junk food marketed to children.
- In the past few decades male sperm counts fell by 50 percent, women's tubal pregnancies increased by 400 percent, and girls eight years old and younger began experiencing puberty. Chemicals are redefining what is "normal"
| Editorial Review:
In 1906, Congress passed the US Food and Drug Act and, according to the author, this has led to the "Hundred-Year Lie" that our food and drugs have been investigated and are safe and that the additives and chemicals put in them may actually make them better than the organic, natural variety. As an investigative reporter, Fitzgerald is expert at using scientific documents, articles in science and environmental journals and expert interviews to support his case. He concludes that we cannot rely on the government, science or manufacturers to either protect us or predict the effects of the products we ingest. As a test, Fitzgerald had his own blood analyzed for toxins and, in spite of living in an area of California known for its pure water and air and careful eating habits, he was shocked to find many toxic chemicals in his blood. While many readers will not agree with his conclusion that "Merely by choosing a diet of pure foods and a lifestyle free of synthetics, we can detoxify ourselves and initiate the healing of many degenerative illnesses and diseases," this book will cause any reader to think about the effect of our own voluntary actions on the health of our bodies. His suggestions for practical steps one can take may prove useful as well, although in the paperback afterword, he fears that denial will prevent most people or governments from taking any significant action.
Reviewer: Nola Theiss (Vol. 42, No. 1) |
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