How does electrolysis of water produce hydrogen and oxygen?

Electrolysis is a process that uses electric current to drive a chemical change, specifically an oxidation-reduction reaction, within an electrolytic cell.12

When water is subjected to electrolysis, it is decomposed into hydrogen and oxygen gases. The process functions as follows:1

• The Setup: Two electrodes—a negatively charged cathode and a positively charged anode—are placed into the water.12
• Reduction at the Cathode: Electric current delivers electrons to the cathode. Components of the solution migrate to this electrode, combine with the electrons, and undergo reduction to form neutral elements or molecules.12
• Oxidation at the Anode: Simultaneously, components of the solution migrate to the anode, where they give up electrons and undergo oxidation to form neutral elements or molecules.12

By supplying electrical energy, the cell forces these reactions to occur, effectively splitting the water molecules into their constituent gases.12