Pattern
The basic understanding of pattern is the organization of a surface or structure that is repeating. A pattern does not have movement, but it may or may not have rhythm. Pattern will follow a sequence based on shapes, lines and/or color as seen on the pictures below.
The picture above shows a pattern of both color and shape. The color pattern is orange and yellow with light blue and dark blue. Orange and yellow pop out the most and follow a specific order; the yellow is always on the bottom half of the diamond while the orange is on the top half. This sequence is never broken. The dark blue and the light blue also follow the lighter colors, but just rotated; the dark blue is always on the right while the light blue is always on the left. the pattern that is associated with shape is the diamonds and triangles. the triangles follow the color pattern and face a specific direction depending on what its color is. the diamonds are two of the four colors paired with each other; one based on primary and secondary color (orange and yellow) while the other is based on a tint and a shade (dark and light blue).
The image above is a pattern based on lines and follows a sequence where the vertical lines are evenly spaced and the waves are overlapping each other. The waves form an oval with sharp points that intersect a vertical line (not every one) while its "peaks" and "valleys" touch every other of these lines. This sequence continues throughout the image creating the patterns appearance.
This piece does not focus on pattern, and not all pieces of artwork do, but they can still use one of the principles to make masterpiece. The colors are not the focus point of pattern, but the organization of the rectangles are used in an ongoing sequence that creates a pattern. Each rectangle flips at its current angle which allows it to follow an organization which makes it a pattern.