Pixels and colours

New idea

Your screen is a mosaic

Put a drop of water on your phone screen and look through it. The smooth picture breaks into a grid of tiny coloured squares.

Each square is a pixel (short for picture element). A pixel shows just one colour at a time, but millions of them side by side fool your eyes into seeing a photo.

A Full HD screen is 1920 pixels across and 1080 pixels down. The computer has to decide the colour of every single one.