What is the concept of zentangle art

The Zen tangle Method is an easy-to-learn, relaxing, and fun way to create beautiful images by drawing structured patterns. We call these patterns, tangles. You create tangles with combinations of dots, lines, simple curves, S-curves and orbs. These simple shapes are the "Elemental Strokes" in all Zen tangle art.

Explanation:

in the image below

Explanation:

based on the images pictured above, the major difference between the two cathedrals: the cathedral of notre dame and the amiens cathedral, is that the cathedral of notre dame emphasizes the horizontal lines while the amiens cathedral emphasizes the vertical lines.