The difference between fumigation and fogging lies in the scope and delivery method. Fumigation involves using a gas that permeates an entire structure, effectively eliminating pests in hidden areas like walls or wood. Fogging disperses a fine mist of liquid pesticide over a localized area, mainly targeting surface-level or airborne pests. Fumigation is comprehensive and often used for severe infestations, while fogging is more localized and suitable for flying insects or smaller pest issues.