Resistance is easy to understand. Ohms is the unit in which resistance is measured. The lower the resistance, the higher the power will be, and the higher the resistance, the lower the power. The higher the power, the more vapour is produced. High resistance coils are generally MTL coils (higher than 1.0ohms) that provide a cigarette-style experience and are used with higher nicotine strengths. Lower resistance coils (below 1.0ohms) are sub-ohm coils that provide you with more power and vapour and should be used with low nicotine strengths.