Bomb A bomb is any of a range of explosive weapon s that only rely on the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy ( an explosive device ) . Detonation s inflict damage principally through ground - and atmosphere - transmitted mechanical stress , the impact and penetration of pressure - driven projectiles , pressure damage , and explosion - generated effects . A nuclear weapon employs chemical - based explosives to initiate a much larger nuclear - based explosion . Bombs have been in use since the 11th century in Song Dynasty China . The term bomb is not usually applied to explosive devices used for civilian purposes such as construction or mining , although the people using the devices may sometimes refer to them as " bomb " . The military use of the term " bomb " , or more specifically aerial bomb action , typically refers to airdropped , unpowered explosive weapons most commonly used by air force s and naval aviation . Other military explosive weapons not classified as " bombs " include grenade s , shells , depth charge s ( used in water ) , warhead s when in missile s , or land mine s . In unconventional warfare , " bomb " can refer to a range of offensive weaponry . For instance , in recent conflicts , " bombs " known as improvised explosive device s ( IEDS ) have been employed by insurgent fighters to great effectiveness . The word comes from the Latin " bombus " , which in turn comes from the Greek βόμβος ( " bombos " ) , an onomatopoetic term meaning " booming " , " buzzing " . History . Explosive bombs were used in China in 1221 , by a Jin Dynasty army against a Song Dynasty city . Bombs built using bamboo tubes appear in the 11th century . Bombs made of cast iron shells packed with explosive gunpowder date to 13th century China . The term was coined for this bomb ( i . e . " thunder - crash bomb " ) during a Jin Dynasty ( 1115 – 1234 ) naval battle of 1231 against the Mongols . The " History of Jin " 《 金史 》 ( compiled by 1345 ) states that in 1232 , as the Mongol general Subutai ( 1176 – 1248 ) descended on the Jin stronghold of Kaifeng , the defenders had a " thunder - crash bomb " which " consisted of gunpowder put into an iron container . . . then when the fuse was lit ( and the projectile shot off ) there was a great explosion the noise whereof was like thunder , audible for more than a hundred " li " , and the vegetation was scorched and blasted by the heat over an area of more than half a " mou " . When hit , even iron armour was quite pierced through . " The Song Dynasty ( 960 – 1279 ) official Li Zengbo wrote in 1257 that arsenal s should have several hundred thousand iron bomb shells available and that when he was in Jingzhou , about one to two thousand were produced each month for dispatch of ten to twenty thousand at a time to Xiangyang and Yingzhou . The Ming Dynasty text " Huolongjing " describes the use of poisonous gunpowder bombs , including the " wind - and - dust " bomb . During the Mongol invasions of Japan , the Mongols used the explosive " thunder - crash bombs " against the Japanese . Archaeological evidence of the " thunder - crash bombs " has been discovered in an underwater shipwreck off the shore of Japan by the Kyushu Okinawa Society for Underwater Archaeology . X - rays by Japanese scientists of the excavated shells confirmed that they contained gunpowder . Shock . Explosive shock waves can cause situations such as body displacement ( i . e . , people being thrown through the air ) , dismemberment , internal bleeding and ruptured eardrum s . Shock waves produced by explosive events have two distinct components , the positive and negative wave . The positive wave shoves outward from the point of detonation , followed by the trailing vacuum space " sucking back " towards the point of origin as the shock bubble collapses . The greatest defense against shock injuries is distance from the source of shock . As a point of reference , the overpressure at the Oklahoma City bombing was estimated in the range of Heat . A thermal wave is created by the sudden release of heat caused by an explosion . Military bomb tests have documented temperatures of up to 2 , 480 °C ( 4 , 500 °F ) . While capable of inflicting severe to catastrophic burns and causing secondary fires , thermal wave effects are considered very limited in range compared to shock and fragmentation . This rule has been challenged , however , by military development of thermobaric weapon s , which employ a combination of negative shock wave effects and extreme temperature to incinerate objects within the blast radius . This would be fatal to humans , as bomb tests have proven . Fragmentation . Fragmentation is produced by the acceleration of shattered pieces of bomb casing and adjacent physical objects . The use of fragmentation in bombs dates to the 14th century , and appears in the Ming Dynasty text " Huolongjing " . The fragmentation bombs were filled with iron pellets and pieces of broken porcelain . Once the bomb explodes , the resulting shrapnel is capable of piercing the skin and blinding enemy soldiers . While conventionally viewed as small metal shards moving at super - supersonic and hypersonic speeds , fragmentation can occur in epic proportions and travel for extensive distances . When the S . S . Grandcamp exploded in the Texas City Disaster on April 16 , 1947 , one fragment of that blast was a two ton anchor which was hurled nearly two miles inland to embed itself in the parking lot of the Pan American refinery . Fragmentation should not be confused with shrapnel , which relies on the momentum of a shell to cause damage . Effects on living things . To people who are close to a blast incident , such as bomb disposal technicians , soldiers wearing body armor , deminers or individuals wearing little to no protection , there are four types of blast effects on the human body : overpressure ( shock ) , fragmentation , impact and heat . Overpressure refers to the sudden and drastic rise in ambient pressure that can damage the internal organs , possibly leading to permanent damage or death . Fragmentation includes the shrapnel described above but can also include sand , debris and vegetation from the area surrounding the blast source . This is very common in anti - personnel mine blasts . The projection of materials poses a potentially lethal threat caused by cuts in soft tissues , as well as infections , and injuries to the internal organs . When the overpressure wave impacts the body it can induce violent levels of blast - induced acceleration . Resulting injuries range from minor to unsurvivable . Immediately following this initial acceleration , deceleration injuries can occur when a person impacts directly against a rigid surface or obstacle after being set in motion by the force of the blast . Finally , injury and fatality can result from the explosive fireball as well as incendiary agents projected onto the body . Personal protective equipment , such as a bomb suit or demining ensemble , as well as helmets , visors and foot protection , can dramatically reduce the four effects , depending upon the charge , proximity and other variables . Types . Experts commonly distinguish between civilian and military bombs . The latter are almost always mass - produced weapons , developed and constructed to a standard design out of standard components and intended to be deployed in a standard explosive device . IED s are divided into three basic categories by basic size and delivery . Type 76 , IEDs are hand - carried parcel or suitcase bombs , type 80 , are " suicide vests " worn by a bomber , and type 3 devices are vehicles laden with explosives to act as large - scale stationary or self - propelled bombs , also known as VBIED ( vehicle - borne IEDs ) . Improvised explosive materials are typically very unstable and subject to spontaneous , unintentional detonation triggered by a wide range of environmental effects ranging from impact and friction to electrostatic shock . Even subtle motion , change in temperature , or the nearby use of cellphones or radios , can trigger an unstable or remote - controlled device . Any interaction with explosive materials or devices by unqualified personnel should be considered a grave and immediate risk of death or dire injury . The safest response to finding an object believed to be an explosive device is to get as far away from it as possible . Atomic bombs are based on the theory of nuclear fission , that when a large atom splits it releases a massive amount of energy . Hydrogen bomb s use the energy from an initial fission explosion to create an even more powerful fusion explosion . The term dirty bomb refers to a specialized device that relies on a comparatively low explosive yield to scatter harmful material over a wide area . Most commonly associated with radiological or chemical materials , dirty bombs seek to kill or injure and then to deny access to a contaminated area until a thorough clean - up can be accomplished . In the case of urban settings , this clean - up may take extensive time , rendering the contaminated zone virtually uninhabitable in the interim . The power of large bombs is typically measured in kilotons ( kt ) or megatons of TNT ( Mt ) . The most powerful bombs ever used in combat were the two atomic bombs dropped by the United States to attack Hiroshima and Nagasaki , and the most powerful ever tested was the Tsar Bomba . The most powerful non - nuclear bomb is Russia n " Father of All Bombs " ( officially Aviation Thermobaric Bomb of Increased Power ( ATBIP ) ) followed by the United States Air Force ' s MOAB ( officially Massive Ordnance Air Blast , or more commonly known as the " Mother of All Bombs " ) . Below is a list of five different types of bombs based on the fundamental explosive mechanism they employ . Compressed Gas . Relatively small explosions can be produced by pressurizing a container until catastrophic failure such as with a dry ice bomb . Technically , devices that create explosions of this type can not be classified as " bombs " by the definition presented at the top of this article . However , the explosions created by these devices can cause property damage , injury , or death . Flammable liquids , gasses and gas mixtures dispersed in these explosions may also ignite if exposed to a spark or flame . Low Explosive . The simplest and oldest type of bombs store energy in the form of a low explosive . Black powder is an example of a low explosive . Low explosives typically consist of a composition of an oxidizing salt , such as potassium nitrate , and solid fuel , such as charcoal or aluminum powder . These compositions deflagrate upon ignition producing hot gas . Under normal circumstances deflagration occurs too slowly to produce a significant pressure wave . Low explosives must , therefore , be used in large quantities or confined in a container with a high burst pressure to be used as a bomb . High Explosive . A high explosive bomb is one that employs a process called " detonation " to rapidly release its chemical energy . Detonation is distinct from deflagration in that the chemical reaction propagates faster than the speed of sound ( often many times faster ) in an intense shock wave . Therefore , the pressure wave produced by a high explosive is not significantly increased by confinement as detonation occurs so quickly that the resulting plasma does not expand much before all the explosive material has reacted . This has led to the development of plastic explosive . A casing is still employed in some high explosive bombs , but with the purpose of fragmentation . Most high explosive bombs consist of an insensitive secondary explosive that must be detonated with a blasting cap containing a more sensitive primary explosive . Nuclear Fission . Nuclear fission type atomic bombs utilize the energy present in very heavy atomic nuclei , such as U - 235 or Pu - 239 . In order to release this energy rapidly , a certain amount of the fissile material must be very rapidly consolidated while being exposed to a neutron source . If consolidation occurs slowly , repulsive forces drive the material apart before a significant explosion can occur . Under the right circumstances , rapid consolidation can provoke a chain reaction that can proliferate and intensify by many orders of magnitude within microseconds . The energy released by a nuclear fission bomb may be tens of thousands of times greater than a chemical bomb of the same mass . Nuclear Fusion . Nuclear fusion type atomic bombs release energy through the fusion of the light atomic nuclei of deuterium and tritium . With this type of bomb , a thermonuclear detonation is triggered by the detonation of a fission type nuclear bomb contained within a material containing high concentrations of deuterium and tritium . Weapon yield is typically increased with a tamper that increases the duration and intensity of the reaction through inertial confinement and neutron reflection . Nuclear fusion bombs can have arbitrarily high yields making them hundreds or thousands of times more powerful than nuclear fission bombs . Other . Concrete bomb . A concrete bomb is an aerial bomb which contains dense , inert material ( typically concrete ) instead of explosive . The target is destroyed using the kinetic energy of the falling bomb . Inert bomb . An inert munition is one whose inner energetic material has been removed or otherwise rendered harmless . Inert munitions are used in military and naval training , and they are also collected and displayed by public museums , or by private parties . Typically , American and NATO inert munitions are painted entirely in light blue and / or have the word " INERT " stenciled on them in prominent locations . Delivery . The first air - dropped bomb s were used by the Austrians in the 1849 siege of Venice . Two hundred unmanned balloons carried small bombs although few bombs actually hit the city . The first bombing from a fixed - wing aircraft took place in 1911 when the Italians bombed the Turkish lines in what is now Libya , during the Italo - Turkish War . The bombs were dropped by hand . The first large scale dropping of bombs took place during World War I starting in 1915 with the German Zeppelin Airship raids on London , England . One raid on the 8th of September 1915 dropped of high explosives and incendiary bombs , including one bomb which weighed . Modern military bomber aircraft are designed around a large - capacity internal bomb bay while fighter bombers usually carry bombs externally on pylons or bomb racks , or on multiple ejection racks which enable mounting several bombs on a single pylon . Modern bombs , precision - guided munition s , may be guided after they leave an aircraft by remote control , or by autonomous guidance . Some bombs are equipped with a parachute , such as the World War II " parafrag " , which was an 11 kg fragmentation bomb , the Vietnam war - era daisy cutter s , and the bomblets of some modern cluster bomb s . Parachutes slow the bomb ' s descent , giving the dropping aircraft time to get to a safe distance from the explosion . This is especially important with airburst nuclear weapons , and in situations where the aircraft releases a bomb at low altitude . A hand grenade is delivered by being thrown . Grenades can also be projected by other means , such as being launched from the muzzle of a rifle , as in the rifle grenade or using a grenade launcher such as the M203 or by attaching a rocket to the explosive grenade as in a rocket - propelled grenade ( RPG ) . A bomb may also be positioned in advance and concealed . A bomb destroying a rail track just before a train arrives causes a train to derail . Apart from the damage to vehicles and people , a bomb exploding in a transport network often also damages , and is sometimes mainly intended to damage that network . This applies for railways , bridges , runways , and ports , and to a lesser extent , depending on circumstances , to roads . In the case of suicide bombing the bomb is often carried by the attacker on his or her body , or in a vehicle driven to the target . The Blue Peacock nuclear mines , which were also termed " bombs " , were planned to be positioned during wartime and be constructed such that , if they were disturbed , they would explode within ten seconds . The explosion of a bomb may be triggered by a detonator or a fuse . Detonators are triggered by clock s , remote control s like cell phones or some kind of sensor , such as pressure ( altitude ) , radar , vibration or contact . Detonators vary in ways they work , they can be electrical , fire fuze or blast initiated detonators and others , Blast seat . In forensic science , the point of detonation of a bomb is referred to as its blast seat , seat of explosion , blast hole or epicenter . Depending on the type , quantity and placement of explosives , the blast seat may be either spread out or concentrated ( i . e . , an explosion crater ) . Other types of explosion s , such as dust or vapor explosions , do not cause craters or even have definitive blast seats .