An HHO or Brown gas generator is an interesting and often misunderstood technology.
The Brown gas generator uses electrolysis to split water (H2O) into it´s base molecules, 2 hydrogen and 1 oxygen molecule.
This is why it is often referred to as an HHO gas generator.
Step 1: Stuff you'll need
An empty cup
Dc 5v power supply (You can also use batteries)
Two plated nails
Two rubber washers
Stripped copper wires