1.)  What was Photoshop based off of in traditional photography?

To turn the immage to grayscale.

2.)  Who were the two people that combined knowledge to create Photoshop?

Thomas Knoll

3.)  What year was Photoshop 1.0 released?

1990

4.)  What feature was added to Photoshop 2.0?

The path feature.

5.)  When was the layers feature introduced and what are layers?

1996. Allows you to map a series of commands to one command.

6.)  When did the unification in the Photoshop interface happen?

2007

7.)  When did the lasso selection tool and the history feature appear?

1990