Figure and Ground
At times this is a simple concept in works such as this piece by Naomi from Workingwoman on Etsy. What makes the figure stand out so well is the vast emptiness surrounding the boater. That emptiness is the ground and it helps to anchor the focal point for the eye. Another example would be this piece by DianeMartinStudio on Etsy where the eye travels between the red hearts and the face of the crow. The rest is lost in the background due to boldness of the three focal points.
Frame & Surface
Frame and surface are important concepts in the composition of a piece. Its necessary to understand that positioning of the focal point or of lines when composing a piece can bring visual balance causing the work to be pleasing on the eye. The Woman in red by Andrew Atroshenko shows a fibonacci spiral overlaying it and demonstrates how this composition follows the pleasing lines of this naturally occurring shape. The stacked rocks on the right demonstrate use of 'The rule of Thirds' using lines to break up the photo into nine equally proportioned block by drawing two horizontal lines and two vertical lines. When compositions follow those lines or intersecting points, it often causes a sense of balance in the piece.
Mark & Line
There are many methods to creating art, marks and lines are basic concepts that explain different styles in designing a piece. Marks on a piece can imply line and shape while lines can shape and contain the basic to the complex and has been used as long as people have had a media to drag across a surface.