Line is the most recognizable of design elements. The quality or contour of a line is a powerful visual ingredient, and contains potential for unlimited expression. Words often used to describe line quality are thin, thick, rough or smooth.
Steed is my favorite New Yorker cartoonist. His nervous, unpredictable line quality makes me laugh before I read the joke.
I recently saw Bennett Bossert's artwork as I was thinking about line quality. His even, consistent line often give his large drawings a floating, wave like feel.
Rough translation from German: "The druggist and his medicinal herbs know what to do." What's not to like about these organic, branching lines?