Self-cleaning surfaces are materials designed to repel dirt, dust, and stains, making them easier to maintain. These surfaces often use special coatings that utilize properties like hydrophobicity or photocatalysis. Hydrophobic surfaces repel water, causing it to bead up and roll off, taking dirt with it. Photocatalytic surfaces use light to break down organic materials, effectively cleaning themselves over time. Common applications of self-cleaning surfaces include windows, solar panels, and building facades. These surfaces can reduce the need for harsh cleaning chemicals and frequent maintenance, contributing to a more sustainable and efficient cleaning process.