Adobe Illustrator started as a commercialization of Adobe's in-house font development software and PostScript file format. It is the companion product of Adobe Photoshop's digital photo manipulation and photorealistic computer illustration, with Illustrator providing the typesetting and logo graphic  design. Illustrator 88,  version 1.7, introduced many new tools and features. Early versions of the software did not support working in preview mode and users needed to have two windows open on their desktop in order to have a live preview of their work. One window would show the work in progress and the other window would show a preview of the work in progress.

Its early versions were primarily for Macintosh, but In the early 1990s, Adobe released versions for NeXT, Digital Equipment Corporation Ultrix, Silicon Graphics IRIX, and Sun Solaris platforms, but these were discontinued due to poor sales. The first version of Illustrator for Windows, version 2.0, was unsuccessfully released in early 1989. Version 4 was the first version with editing in preview mode, which did not appear in a Macintosh version until 5.0 in 1993. Version 6 was the last Macintosh version as the user interface changed radically to bring consistency between Mac and Windows. 

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