A xenon arc lamp is a special kind of light bulb that makes really bright light by using a gas called xenon. It's like a regular light bulb, but instead of heating up a tiny wire called a filament to make light, it heats up gas. This gas is very special because it glows very brightly when it's heated up. It's kind of like how a campfire glows brightly when you add more wood to it.
The xenon gas is filled into a special container that has two electrodes (kind of like metal pins) at either end. When a special type of electricity is sent through these electrodes, it makes the xenon gas inside the container really hot, and it starts to glow super bright. This makes it perfect for special kinds of lights that need really bright light, like in movie projectors or certain scientific experiments.
So there you have it, a xenon arc lamp is a special kind of light bulb that uses a special gas called xenon to make really bright light by heating up the gas with electricity.