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PostScript (PS) is a computer language for creating vector graphics. It is a dynamically typed, concatenative programming language and was created by John Warnock, Charles Geschke, Doug Brotz, Ed Taft and Bill Paxton〔https://www.adobe.com/products/postscript/pdfs/postscript_is_20.pdf〕 in 1982. It is used as a page description language in the electronic and desktop publishing areas. == History == The concepts of the PostScript language were seeded in 1976 when John Warnock was working at Evans & Sutherland, a computer graphics company. At that time John Warnock was developing an interpreter for a large three-dimensional graphics database of New York harbor. Warnock conceived the Design System language to process the graphics. Concurrently, researchers at Xerox PARC had developed the first laser printer and had recognized the need for a standard means of defining page images. In 1975-76 Bob Sproull and William Newman developed the Press format, which was eventually used in the Xerox Star system to drive laser printers. But Press, a data format rather than a language, lacked flexibility, and PARC mounted the Interpress effort to create a successor. In 1978 Evans & Sutherland asked Warnock to move from the San Francisco Bay Area to their main headquarters in Utah, but he was not interested in moving. He then joined Xerox PARC to work with Martin Newell. They rewrote Design System to create J & M (for "John and Martin") which was used for VLSI design and the investigation of type and graphics printing. This work later evolved and expanded into the Interpress language. Warnock left with Chuck Geschke and founded Adobe Systems in December 1982. They, together with Doug Brotz, Ed Taft and Bill Paxton created a simpler language, similar to Interpress, called PostScript, which went on the market in 1984. At about this time they were visited by Steve Jobs, who urged them to adapt PostScript to be used as the language for driving laser printers. In March 1985, the Apple LaserWriter was the first printer to ship with PostScript, sparking the desktop publishing (DTP) revolution in the mid-1980s. The combination of technical merits and widespread availability made PostScript a language of choice for graphical output for printing applications. For a time an interpreter (sometimes referred to as a RIP for Raster Image Processor) for the PostScript language was a common component of laser printers, into the 1990s. However, the cost of implementation was high; computers output raw PS code that would be interpreted by the printer into a raster image at the printer's natural resolution. This required high performance microprocessors and ample memory. The LaserWriter used a 12 MHz Motorola 68000, making it faster than any of the Macintosh computers to which it attached. When the laser printer engines themselves cost over a thousand dollars the added cost of PS was marginal. But as printer mechanisms fell in price, the cost of implementing PS became too great a fraction of overall printer cost; in addition, with desktop computers becoming more powerful, it no longer made sense to offload the rasterisation work onto the resource-constrained printer. By 2001, few lower-end printer models came with support for PostScript, largely due to growing competition from much cheaper non-PostScript ink jet printers, and new software-based methods to render PostScript images on the computer, making them suitable for any printer; PDF, a descendant of PostScript, provides one such method, and has largely replaced PostScript as ''de facto'' standard for electronic document distribution. On high-end printers, PostScript processors remain common, and their use can dramatically reduce the CPU work involved in printing documents, transferring the work of rendering PostScript images from the computer to the printer. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「PostScript」の詳細全文を読む スポンサード リンク
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