"Photoshop, Illustrator, And InDesign: What’s The Diff?" This article provides a useful explanation of the general difference between the various software types and which is best for various tasks.
"GIF, JPEG, and PNG: What’s The Difference?" This article defines various image formats and describes which format is best for various image types and how they will be output.
"Vector And Rastor: What’s The Difference?" This article describes the difference between the two types of software.
"Differences between RGB and CMYK Color Modes" As the title suggests...