The iPhone 18 Pro's Rumored Camera Upgrade, Explained

Apple's upcoming iPhone 18 Pro and iPhone 18 Pro Max are expected to feature a variable-aperture camera. The upgrade has been rumored repeatedly and would be a first for Apple's smartphone lineup, but what would it actually change for everyday users?
An aperture is the opening inside a camera lens that lets in light. A natural comparison would be the pupils of your eyes, which open wider in the dark and become smaller in bright conditions.Current iPhone cameras have an opening that's fixed to th