the.com/rule of thirds

means A composition guideline suggesting you place key elements along imaginary lines dividing an image into thirds, rather than dead center, for a more balanced and visually interesting result.

from Codified as a painting principle in the late 1700s — writer and amateur painter John Thomas Smith described dividing a canvas into thirds in his 1797 treatise on landscape, building on older artistic intuitions about balance that painters had followed for generations. The 'rule' got its name and spread widely once photography arrived, as a teachable shortcut for framing a shot without a formal art education. It's less a law than a well-worn habit dressed up as one.