Generally speaking, any graphic artist who has the ability to generate visual images using pen, paint, computer graphics programs, collages, etc., to communicate a pictorial message or visually complement accompanying text material. An illustrator is distinguished from a photographer in that the former typically relies on the generation of images by hand (using a variety of mechanical and/or electronic tools), rather than photographing something.
The term Illustrator (capitalized) also refers to a popular software program developed by Adobe Systems, Inc., which allows those who have mastered the program's intricacies to create vector-based line art and illustrations, which can then be saved as EPS files and imported into page make-up (or other) programs. The earliest versions of Illustrator pioneered the use of vector-based drawings and although there are many similar programs currently on the market, Adobe Illustrator is still the most versatile and complex. Versions of Illustrator are available for most major computer platforms.