What is Computer?

Personal computer

From Wikipedia, the free encyclopedia

Personal computer

An illustration of a modern personal desktop computer

A personal computer (PC) is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator. In contrast, the batch processing or time-sharing models allowed large expensive mainframe systems to be used by many people, usually at the same time. Large data processing systems require a full-time staff to operate efficiently.
Software applications for personal computers include, but are not limited to, word processing, spreadsheets, databases, Web browsers and e-mail clients, digital media playback, games, and myriad personal productivity and special-purpose software applications. Modern personal computers often have connections to the Internet, allowing access to the World Wide Web and a wide range of other resources. Personal computers may be connected to a local area network (LAN), either by a cable or a wireless connection. A personal computer may be a desktop computer or a laptop, tablet PC, or a handheld PC.
While early PC owners usually had to write their own programs to do anything useful with the machines, today's users have access to a wide range of commercial software and free software, which is provided in ready-to-run or ready-to-compile form. Since the 1980s, Microsoft and Intel have dominated much of the personal computer market, first with MS-DOS and then with the Wintel platform. Alternatives to Windows include Apple's Mac OS X and the open-source Linux OSes. AMD is the major alternative to Intel. Applications and games for PCs are typically developed and distributed independently from the hardware or OS manufacturers, whereas software for many mobile phones and other portable systems is approved and distributed through a centralized online store.
In July & August 2011, marketing businesses and journalists started to talk about the 'Post-PC Era', an era where the desktop form factor was being replace with more portable computing such as netbooks, and Tablet PC's.

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Computer recycling

From Wikipedia, the free encyclopedia

  (Redirected from Laptops-Recycling)

Computer monitors are typically packed into low stacks on wooden pallets for recycling and then shrink-wrapped.

Computer recycling or electronic recycling is the recycling or reuse of computers or other electronics. It includes both finding another use for materials (such as donation to charity), and having systems dismantled in a manner that allows for the safe extraction of the constituent materials for reuse in other products.

Reasons for recycling

Obsolete computers or other electronics are a valuable source for secondary raw materials, if treated properly; if not treated properly, they are a source of toxins and carcinogens. Rapid technology change, low initial cost, and even planned obsolescence have resulted in a fast-growing surplus of computer or other electronic components around the globe. Technical solutions are available, but in most cases a legal framework, a collection system, logistics, and other services need to be implemented before a technical solution can be applied. According to the U.S. Environmental Protection Agency, an estimated 30 to 40 million surplus PCs, which it classifies under the term "hazardous household waste", will be ready for end-of-life management in each of the next few years. The U.S. National Safety Council estimates that 75% of all personal computers ever sold are now surplus electronics.
In 2007, the United States Environmental Protection Agency (EPA) said that more than 63 million computers in the U.S. were traded in for replacements—or they simply were discarded. Today 15 percent of electronic devices and equipment are recycled in the United States. Most electronic waste is sent to landfills or becomes incinerated, having a negative impact on the environment by releasing materials such as lead, mercury, or cadmium into the soil, groundwater, and atmosphere.
Many materials used in the construction of computer hardware can be recovered in the recycling process for use in future production. Reuse of tin, silicon, iron, aluminum, and a variety of plastics — all present in bulk in computers or other electronics — can reduce the costs of constructing new systems. In addition, components frequently contain copper, gold, and other materials valuable enough to reclaim in their own right.

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pc

It’s designed to be a better computer.

When you buy a computer, you want it to last. And a Mac will. That’s because a Mac is designed and built to be as reliable as it is beautiful.

Designed to last.

A Mac is designed for a long, productive life. Apple designers and engineers spend countless hours ensuring that each Mac is precisely built — inside and out. From the down-to-the-micron fit of each internal component to the finish of the enclosure, every detail matters. Take MacBook Pro, for example. Its unibody enclosure is machined from a solid block of aluminum. The result is a MacBook Pro that is thin and light, looks polished and refined, and feels strong and durable.
Watch the unibody video

Born to perform.

To make a better computer, only quality components and materials will do. That’s why every Mac contains a hard drive, memory, graphics processor, even a power supply specifically chosen to give you the best performance possible. And materials like aluminum and glass (in iMac and MacBook Pro) or rugged polycarbonate (in MacBook) keep all those high-performance components safe and sound.

Charge today and five years from today.

Getting a few hours of battery life from a notebook is good. But for a Mac, good isn’t good enough. On a single charge, you can get up to 8-9 hours on the 15- and 17-inch MacBook Pro, and up to 10 hours on the MacBook and 13-inch MacBook Pro.¹ That means you can power through a day of work or a day of classes without stopping to find the nearest outlet. And the battery inside MacBook and MacBook Pro can be recharged up to 1000 times — good for about five years of typical usage — and lasts nearly three times the lifespan of typical notebook batteries.

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