The following treaties are generally considered in effect for the entire world, and cover even those countries which have not signed or ratified them:
- The Hague Conventions of 1899 or 1907
- Chemical Weapon Convention
- several of the Geneva Conventions
- Biological Weapon Convention
- The Geneva Protocol
- The Convention on Certain Weapons
There are several categories of weapons which are forbidden from use (note, that none of these treaties name specific weapons, only categories).
- Poisoned weapons
- Weapons which cause excessive pain or superfluous injury ( the modern definition here is those weapons which cause more injury than minimally required to incapacitate)
- Any weapon employed on or by a vessel, vehicle, or individual carrying the Red Cross or Red Crescent mark. (The Red Cross/Crescent is a universally protected sign, and no weapon may be used for any purpose either by something carrying that sign, or against one marked with the sign).
- Use of gases which cause asphyxiation or severe injury
- Bullets which cause excessive injury, especially those of an explosive or expanding nature (hollow-points).
- Any biological or chemical weapon
- Laser weapons intended to blind
- Weapons which produce fragments not detectable by X-rays
- Land mines which do no automatically self-destruct after a limited time period, or which are constructed of materials not detectable by normal methods (e.g. plastics)
Certain weapons which might be perceived to be covered under the above generalization are not usually considered banned, or are restricted according to their use.
- Tear gas and similar gases which produce mild and temporary effects are generally not considered a Chemical weapon.
- Incendiary weapons (napalm, flamethrowers, thermite, white phosphorous, etc.) are not banned, but are banned in their use on or near civilians.
- Genetic weapons (those tailored to affect only certain peoples of a specific genetic makeup) are considered to be banned, though inferentially, under the Biological Weapons Convention.
- Use of weapons such as those made from Depleted Uranium which have a possible localized toxic side effect are permitted.
In addition, the Ottawa Treaty (Convention on the Prohibition of the Use, Stockpiling, Production and Transfer of Anti-Personnel Mines and on their Destruction) bans all land mines. This will cover most of the world, though there are several major non-signatories.
The new Convention on Cluster Munitions will take affect in 2010, and ban all cluster bombs and similar weapons which do not meet very strict requirements of size, ability to be detected, and other limits. This treaty currently has a limited number of signatories, though it is expected to grow slowly.