Spring-Loaded
Spring-loaded Airsoft guns are considered to be good beginner guns for people new to the sport. They are often significantly less expensive than their electric and gas-powered counterparts, making them the preferred choice for anyone still exploring their interest in Airsoft. The downside is that they must be cocked before every shot. This makes them slow, which is a notable disadvantage in an Airsoft match. The advantage is that they need no outside power source.
Electric
Electric-operated Airsoft guns are the most common gun models on the market. They are the most frequently used because they are moderately priced and can provide the rapid fire effect that spring-loaded models cannot. In an Airsoft match, speed is a valuable defense. The longer it takes a gun to fire, the more vulnerable the user is. The disadvantage is that when the battery runs out, the gun is useless until it is recharged.
Alternatives
A third alternative to spring-loaded or electric power is gas. Pressurized gas, usually a blend of propane and polysiloxane lubricant, is used to propel the pellets and fire the gun. Gas-powered Airsoft guns are the most expensive of the three varieties and are usually reserved for people who are committed to the sport and want the most proficient gun possible. Gas power lends itself best to use in pistols.