Gerber format is a special way of telling a machine how to create an electronic circuit board. Think of it like a coloring book for a machine! Just like you know where to color inside the lines, the machine knows where to put each part of the circuit board.
In Gerber format, each part of the circuit board is shown on a special piece of paper called a "layer". There might be different layers for different things - like one for the copper wires, one for the pads where components like resistors or LEDs will be added, and so on.
When a machine reads the Gerber files, it knows exactly where each layer should go and how it should look. This helps the machine build a perfect circuit board with no mistakes.
So, Gerber format is simply a way to give the machine all the instructions it needs to build a perfect electronic circuit board. Pretty cool, huh?