Adobe Inc. is an American multinational computer software company. Incorporated in Delaware and headquartered in San Jose, California, it has historically focused upon the creation of multimedia and creativity software products, with a more recent foray into digital marketing software. Adobe is best known for its Adobe Flash web software ecosystem, Photoshop image editing software, Adobe Illustrator vector graphics editor, Acrobat Reader, the Portable Document Format , and Adobe Creative Suite, as well as its successor Adobe Creative Cloud. Adobe was founded in December 1982 by John Warnock and Charles Geschke, who established the company after leaving Xerox PARC to develop and sell the PostScript page description language. In 1985, Apple Computer licensed PostScript for use in its LaserWriter printers, which helped spark the desktop publishing revolution.