Painting provides protection and aesthetics for interior and exterior surfaces. Success depends on proper surface preparation, paint selection, and application technique. Surface preparation is critical; inadequate prep causes paint failure and peeling. Existing paint must be cleaned and sanded to remove loose or peeling material. Glossy surfaces must be dulled to improve adhesion. Holes and gaps must be filled with spackling compound or putty. Cracks in drywall must be taped and finished. Priming is recommended for raw wood and drywall, especially for stains or color changes. Primer provides better adhesion and blocks stains from bleeding through. Wood with knots or stains requires stain-blocking primers. Rust on metal requires rust-inhibiting primers. Paint selection depends on location and environmental conditions. Interior paints include latex (water-based) and alkyd (oil-based). Latex paints are fast-drying and low-odor. Alkyd paints provide superior finish quality but require ventilation. Exterior paints must be UV-resistant and flexible to accommodate expansion/contraction. Acrylic latex exterior paints resist weathering well. High-quality paints include better pigments and binders lasting longer before repainting. Application technique affects finish quality. Brushes work well for detail and corners. Rollers speed coverage on large flat areas. Spray application provides uniform finish but requires skill to avoid drips and runs. Proper film thickness ensures durability; insufficient thickness fails prematurely. Curing time before service is important; full cure may require weeks before the paint reaches final hardness. Multiple coats of paint provide better coverage and durability than single coats.