salah al azhari

When a computer connects to a network and begins communicating with others, it is taking a risk. Internet security involves the protection of a computer’s internet account and files from intrusion of an unknown user. Basic security measures involve protection by well selected passwords, change of file permissions and back up of computer’s data.There are many types of viruses, here are some of them: 

• Trojan horses are programs which pretend to do one thing, but in reality snoop out your personal data or damage it. These types conceal their identity or true intentions and are usually quite hard to detect.
• Worms are programs which are able to replicate themselves over a computer network and in turn perform malicious actions. As a result it has the ability to affect other programs on the computer.
• Viruses are programs which are able to log into the personal files on a computer it has affected and as a result, can end up removing all of them. It can have serious side effects on a computers system.
• Malware can be classified as trojans with a limited payload and are often not detected by most antivirus software. They may require the use of other software designed to detect other classes of malware, including spyware.

Software programs such as antivirus software are the most useful in protecting your computer from harmful viruses

coastal erosion: The erosion of the land by the constant battering of the sea, primarily by the processes of hydraulic action, corrasion, attrition, and corrosion. Hydraulic action occurs when the force of the waves compresses air pockets in coastal rocks and cliffs. The air expands explosively, breaking the rocks apart. It is also the force of the water on the cliff. During severe gales this can be as high as 6 tonnes/cm³ – the force of a bulldozer. Rocks and pebbles flung by waves against the cliff face wear it away by the process of corrosion, or abrasion as it is also known. Chalk and limestone coasts are often broken down by solution (also called corrosion). Attrition is the process by which the eroded rock particles themselves are worn down, becoming smaller and more rounded. Frost shattering (or freeze–thaw), caused by the expansion of frozen water in cracks, and biological weathering, caused by the burrowing of rock-boring molluscs and plants, also lead to the breakdown of rock.Where resistant rocks form headlands, the sea erodes the coast in successive stages. First it exploits weaknesses such as faults and cracks to form caves. Then it gradually wears away the interior of the caves and enlarges them. In some cases the roofs may be broken through to form blowholes. In other cases the caves at either side of a headland may unite to form a natural arch. When the roof of the arch collapses, a stack is formed. This may be worn down further to produce a stump. There are good examples of stacks at The Needles, Isle of Wight, England.

The CPU is the brains of the computer. Sometimes referred to simply as the central processor,but more commonly called processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system.On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor. Since the 1970’s the microprocessor class of CPUs has almost completely overtaken all other CPU implementations.

The CPU itself is an internal component of the computer. Modern CPUs are small and square and contain multiple metallic connectors or pins on the underside. The CPU is inserted directly into a CPU socket, pin side down, on the motherboard. Each motherboard will support only a specific type or range of CPU so you must check the motherboard manufacturer’s specifications before attempting to replace or upgrade a CPU. Modern CPUs also have an attached heat sink and small fan that go directly on top of the CPU to help dissipate heat.

Two typical components of a CPU are the following:

• The arithmetic logic unit (ALU), which performs arithmetic and logical operations.
• The control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.

Dean Guitars is owned by Armadillo Enterprises in Tampa, Florida.^[1] They have a 110,000 square foot facility where they produce a line of USA made guitars. They have a line of import models as well. ^[2]

Established in 1976 in Chicago, IL by Dean B. Zelinsky, ^[3][4] Dean Guitars set out to design guitars that defied traditional shapes and created good tone and playability for the guitarist. The original guitars have pointy shaped bodies and are recognizable by their V-shaped headstocks.

In terms of guitars, Dean Guitars are relatively new on the scene. They had their beginnings in 1976 when the teenaged Dean Zelinsky decided he wanted to create a different kind of guitar design than what was present in the market. Dean started to design guitars that would defy traditional shapes and create good tone and playability for the guitarist. His first guitars were v-shaped and pointed which was both a function of design and helped enhance the guitars tone.

It was this shape that both made their name and was also the cause of the company being somewhat slow to catch on. At the time, they were not considered main stream. However, once people learned about them and started testing them in shops, they started to get a following.

After nearly ten years of production, Zelinsky decided that he no longer wanted to manufacture guitars and sold the company. Oscar Medeiros had ownership of the brand name and trademark until the mid 90s. The guitars Medeiros created under the Dean name were also considered quality instruments.

Medeiros stopped manufacturing Dean Guitars in the mid 1990s or so when Armadillo Enterprises purchased the company and began making them. It was not long before they contacted Zelinsky. He worked for the company as an executive and creative director. The presence of Zelinsky at the company lent an authenticity and quality to the brand.^[5]

Dean Zelinsky is back in the guitar market with his new guitar company, DBZ Guitars, which was made public in August 2008. Dean Zelinsky no longer has any affiliation with Dean Guitars.

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