Flash chromatography is a rapid form of column chromatography that uses slightly smaller silica gel particles and pressurized gas to drive the mobile phase through the column. It provides a faster separation than traditional gravity-fed column chromatography, typically separating mixtures in hours rather than days. Flash chromatography systems use pre-packed plastic columns, a pump to push the solvent through under pressure, and fraction collectors. It is well-suited for isolating and purifying natural products, pharmaceutical compounds, lipids, and other small molecules.