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Top 20 computer systems in the World

Top 20 computer systems in the World
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Top 20 computer systems in the World

From soldering irons to SparcStations, from MITS to Macintosh, personal computers have evolved from do-it-yourself kits for electronic hobbyists into machines that practically leap out of the box and set themselves up. What enabled them to get from there to here? Innovation and determination. Here are top 20 systems that made that rapid evolution possible.

MITS Altair 8800

There once was a time when you could buy a top-of-the-line computer for $395. The only catch was that you had to build it yourself. Although the Altair 8800 wasn’t actually the first personal computer (Scelbi Computer Consulting`s 8008-based Scelbi-8H kit probably took that honor in 1973), it grabbed attention. MITS sold 2000 of them in 1975 - more than any single computer before it.

Based on Intel`s 8-bit 8080 processor, the Altair 8800 kit included 256 bytes of memory (upgradable, of course) and a toggle-switch-and-LED front panel. For amenities such as keyboard, video terminals, and storage devices, you had to go to one of the companies that sprang up to support the Altair with expansion cards. In 1975, MITS offered 4- and 8-KB Altair versions of BASIC, the first product developed by Bill Gates` and Paul Allen`s new company, Microsoft.

If the personal computer hobbyists movement was simmering, 1975 saw it come to a boil with the introduction of the Altair 8800.

Apple II

Those of you who think of the IBM PC as the quintessential business computers may be in for a surprise: The Apple II (together with VisiCalc) was what really made people to look at personal computers as business tools, not just toys.

The Apple II debuted at the first West Coast Computer Fair in San Francisco in 1977. With built-in keyboard, graphics display, eight readily accessible expansion slots, and BASIC built-into ROM, the Apple II was actually easy to use. Some of its innovations, like built-in high-resolution color graphics and a high-level language with graphics commands, are still extraordinary features in desk top machines.

With a 6502 CPU, 16 KB of RAM, a 16-KB ROM, a cassette interface that never really worked well (most Apple It ended up with the floppy drive the was announced in 1978), and color graphics, the Apple II sold for $1298.

Commondore PET

Also introduced at the first West Coast Computer Fair, Commondore`s PET (Personal Electronic Transactor) started a long line of expensive personal computers that brought computers to the masses. (The VIC-20 that followed was the first computer to sell 1 million units, and the Commondore 64 after that was the first to offer a whopping 64 KB of memory.)

The keyboard and small monochrome display both fit in the same one-piece unit. Like the Apple II, the PET ran on MOS Technology’s 6502. Its $795 price, key to the Pet’s popularity supplied only 4 KB of RAM but included a built-in cassette tape drive for data storage and 8-KB version of Microsoft BASIC in its 14-KB ROM.

Radio Shack TRS-80

Remember the Trash 80? Sold at local Radio Shack stores in your choice of color (Mercedes Silver), the TRS-80 was the first ready-to-go computer to use Zilog`s Z80 processor.

The base unit was essentially a thick keyboard with 4 KB of RAM and 4 KB of ROM (which included BASIC). An optional expansion box that connected by ribbon cable allowed for memory expansion. A Pink Pearl eraser was standard equipment to keep those ribbon cable connections clean.

Much of the first software for this system was distributed on audiocassettes played in from Radio Shack cassette recorders.

Osborne 1 Portable

By the end of the 1970s, garage start-ups were pass. Fortunately there were other entrepreneurial possibilities. Take Adam Osborne, for example. He sold Osborne Books to McGraw-Hill and started Osborne Computer. Its first product, the 24-pound Osborne 1 Portable, boasted a low price of $1795.

More important, Osborne established the practice of bundling software - in spades. The Osborne 1 came with nearly $1500 worth of programs: WordStar, SuperCalc, BASIC, and a slew of CP/M utilities.

Business was looking good until Osborne preannounced its next version while sitting on a warehouse full of Osborne 1S. Oops. Reorganization under Chapter 11 followed soon thereafter.

Xerox Star

This is the system that launched a thousand innovations in 1981. The work of some of the best people at Xerox PARC (Palo Alto Research Center) went into it. Several of these - the mouse and a desktop GUI with icons - showed up two years later in Apple`s Lisa and Macintosh computers. The Star wasn’t what you would call a commercial success, however. The main problem seemed to be how much it cost. It would be nice to believe that someone shifted a decimal point somewhere: The pricing started at $50,000.


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