Airsoft [aerosférisi in Greek] is a group leisure activity in the form of a game held in a designated space between two or more groups which, in accordance with a number of rules, attempt to achieve objectives by the use of special airguns that fire plastic balls (BBs) mainly of 6 mm diameter. The guns are powered either by batteries or by gas (including CO2 cartridges) and they are safe for the participants, given their particularly low power (approximately 1 Joule). Despite the low power of the guns (pistols or riffles) the players wear always protective glasses.

Airsoft games are similar to paintball ones but there is a significant difference, the hit.  In paintball the hits to the opponent are clearly shown due to the color contained in the plastic ball. On the contrary, in Airsoft the hits are declared by the player that received them making the mutual trust and honesty important factors of the game.

Airsoft began in 1980’s in Japan, where it was illegal to own a weapon and there was enough interest to acquire it. Because of this interest, companies began to produce realistic, spring-operated replicas using plastic balls of 6 or 8 mm diameter. In the mid-1990s, the game of airsoft arrived in USA and Europe.

It is noted that Airsoft includes also the collection of Airsoft guns as static models.

There are three main types of airsoft guns (either pistols or riffles)

• Spring operated guns, which use a spring system to compress the air that is used to fire the round
• Electric (also known as Automatic Electric Guns) guns, which use rechargeable batteries (NiMH or LiPO) to operate an electric motor. The electric motor moves a piston in a system to compress the air needed to fire the round
• Gas operated guns, which use special propellant gas (CO2 cartridges may be used) to fire the pellet

The aforementioned guns can be divided also in the following categories in according with the rate of fire and the cocking mechanism:

• Automatic – when the gun is cocked only once and then it can fire the pellets every time the trigger is pulled by the user
• Semi Automatic – similar mechanism as the Automatic, however only a round is fired every time the trigger is pulled
• Shotguns – when the firing can be done only after the gun is cocked

Airsoft Terrains
There are three main types of terrains where Airsoft games are conducted:

• Woodland
  A field that is a delineated part of a larger forest area and which may contain several natural barriers such as dense vegetation, fallen trees, etc., providing enough free space and excellent opportunities to cover and hide. This field appears in various forms, depending on the terrain's morphology, which may be rocky, sloping, mountainous etc. The engagement distances between the players are usually larger.
• Urban
  They are mainly abandoned buildings clusters. These include: Abandoned buildings, abandoned military bases, abandoned industrial complexes and abandoned hotel complexes. Airsoft activity takes place inside and outside the buildings, in a bounded perimeter space. The engagement distances between the players are usually smaller.
• Close Quarter Battle (CQB)
  CQB terrains are similar to urban ones; however the main difference is that the activity of airsoft is almost always inside the buildings, which are usually bigger dimensions. The engagement distances between the players in this kind of game are almost always very small.