The latest version, Illustrator CS4, is the fourteenth generation in the product line. Numerous new features include multiple artboards in a single document, a "blob brush" that is similar to the brush in Adobe Flash, and support for transparency in gradients among other features.

Version 1 (Illustrator 88)

Adobe Illustrator was first developed for the Apple Macintosh in 1986 (shipping in January 1987) as a commercialization of Adobe's in-house font development software and PostScript file format. Adobe Illustrator is the companion product of Adobe Photoshop. Photoshop is primarily geared toward digital photo manipulation and photorealistic styles of computer illustration, while Illustrator provides results in the typesetting and logo graphic areas of design.

Versions 2–5

Although, during its first decade, Adobe developed Illustrator primarily for Macintosh, it sporadically supported other platforms. In the early 1990s, Adobe released versions of Illustrator for NeXT, Silicon Graphics IRIX, and Sun Solaris platforms, but they were discontinued due to poor market acceptance. The first version of Illustrator for Windows, version 2.0, was released in early 1989 and flopped. The next Windows version, version 4.0, was widely criticized as being too similar to Illustrator 1.1 instead of the Macintosh 3.0 version, and certainly not the equal of Windows' most popular illustration package CorelDraw. (Note that there were no versions 2.0 or 4.0 for the Macintosh - although the second release for the Mac was titled Illustrator 88 - the year of its release.)

Versions 6–10

With the introduction of Illustrator 6 in 1996, Adobe made critical changes in the user interface with regards to path editing (and also to converge on the same user interface as Adobe Photoshop), and many users opted not to upgrade. Illustrator also began to support TrueType, making the "font wars" between PostScript Type 1 and TrueType largely moot. Like Photoshop, Illustrator also began supporting plug-ins, greatly and quickly extending its abilities.

Versions CS–CS4

Illustrator CS2 (version 12) to reflect its integration with the Adobe Creative Suite, was available for both the Mac OS X and Microsoft Windows operating systems. It was the last version for the Mac which did not run natively on both Intel and PowerPC processors. Illustrator CS was the first version to include 3-dimensional capabilities allowing users to extrude or revolve shapes to create simple 3D objects.

Among the new features included in Illustrator CS2 were Live Trace, Live Paint, a control palette and custom workspaces. Live Trace allows for the conversion of bitmap imagery into vector art and improved upon the previous tracing abilities. Live Paint allows users more flexibility in applying color to objects, specifically those that overlap.

CS3 included interface updates to the Control Bar, the ability to align individual points, multiple Crop Areas, the Color Guide panel and the Live Color feature among others.

CS4 was released in October 2008. It features a variety of improvements to old tools along with the introduction of a few brand new tools. The ability to create Multiple Artboards is one of CS4’s main additions.