Pictures, Figures and Drawings

• xview /xv: Interactive image display.
  
  xv understands almost any format and can convert
  from one to another. It also includes many image
  transformation and you can grep a screen-shot.


• convert: Converts image formats and resizes.


• xfig: Drawing program to produce figures.


• xpaint, ...: Paint with spray and color.


• gimp: Like the professional "Paint Shop (Pro)".