To give phones an uninterrupted screen, makers have worked to place the selfie camera beneath the display itself, so the area above it looks like normal screen until the camera is used. This removes the notch or hole that interrupts many phone fronts.
The engineering challenge is letting enough light reach the hidden camera through the screen without harming either image quality or the display. Early versions traded some photo sharpness for the cleaner look, and the technology has improved gradually. It shows how much effort goes into small refinements of a device people hold every day.