Answer:
Harmony is the sense that all of the elements of your design fit together. ... Unity refers to the repetition of particular elements throughout your design — whether they're colors, shapes or materials — to pull the look together. These principles are used to create a sense of cohesion in the space.
What is the difference between “Unity” and “Harmony”? Unity is achieved when each element of a design fits in with the overall concept of the production. It is defined by how those elements relate to the production as a whole. Harmony, on the other hand, is defined by how those same elements relate to each other.
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