Source

History of Photoshop.

Photoshop was made by two Brothers Thomas Knoll and John knoll in 1987. Thomas Knoll was a doctoral candidate at Michigan University. That time he started to write a program in his Macintosh Plus to display grayscale images on a monochrome display. This program caught the attention of his brother John Knoll. John Knoll was an employee at Industrial Light & Magic Company. He (John Knoll) advised Thomas to turn this into a full-fledged image editing program. Then in 1988, Thomas took a six-month break from his studies to cooperate together with his brother John Knoll on the program. After that Thomas renamed the program "ImagePro" but the name was already taken. Later that year Thomas renamed his program as "Photoshop".

He figures out a short-term deal with scanner manufacturer “Barneyscan” to distribute copies of the program with a slide scanner. A total amount of about 200 copies of Photoshop were shipped. During this time John Knoll traveled to Silicon Valley and gave a demonstration of the program to engineers at Apple and Russell Brown (art director at Adobe). Both displays were successful. When all algorithm has done, two brothers Thomas Knoll and John Knoll released the first Photoshop version 0.63 on 2 October 1988.