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Explore the history of war and weapons with our timeline of weapons technology.

Please note, many of the technologies are difficult to attribute, and historical dates are often approximate.

400,000 BC

The earliest evidence of humans using spears, in a part of Germany now near Schöningen (Nature, DOI&colon; 10.1038/385807a0).

However, one population of modern chimpanzees in Senegal uses spears to hunt bushbabies, suggesting the technology may have been used by our most primitive ancestors.

40,000 to 25,000 BC

The atlatl, sometimes dubbed the Stone Age Kalashnikov, throws a flexible dart that can kill a deer at 40 metres. Developed in northern Africa, it spreads throughout the world, being later replaced by the bow and arrow.

23,000 BC

Boomerangs are strongly associated with Australia's Aboriginal people, but were actually used as hunting weapons throughout Europe and Africa. Most boomerangs do not come back when thrown.

The oldest boomerang yet, 23,000 years, was made from a mammoth tusk and discovered in a cave in Poland (Nature, DOI&colon; 10.1038/329436a0).

20,000 BC

The earliest arrowheads date from this time, suggesting that bows and arrows were in use.

Some believe they were invented much earlier, pointing to a single 60,000-year-old stone that may or may not be an arrowhead.

A thorough analysis of projectile points from archaeological digs around the world suggests that projectile weapons were not in widespread use before 50,000 years ago (Journal of Archaeological Science, DOI&colon; 10.1016/j.jas.2005.10.015).

5300 BC

Horses are first domesticated, on the steppes of Kazakhstan.

As well as revolutionising transport in general, horses are instrumental in the history of warfare. Only in the 20th century, with the appearance of rapid-fire weapons such as machine guns, do armies turn away from a reliance on horses.

5000 BC

The Bronze Age enables the development of the first metal daggers, and later swords.

By 1000 BC, swords are intertwined with Celtic mythology and ritual in Britain, reflecting their importance in society. Perhaps echoed by the Excalibur myth, swords are ceremonially placed in rivers, possibly as offerings to gods (see The swords that had to die).

500 BC

The traction trebuchet is thought to have been developed in China around this time. Powered by teams of about a dozen people, it could sling balls of rock as far as 125 metres. Around the same time, the ancient Greeks develop their own siege weapon, the ballista, a kind of scaled-up crossbow.

The traction trebuchet was long considered to be folklore, until a working model was built in 1991 and shown to be effective. It was eventually replaced by the counterweight trebuchet, which is driven by a falling weight rather than manpower, in the Middle Ages.

800 to 1300 AD

Gunpowder is invented in China. This leads rapidly to a primitive firearm, the "fire lance", the first rocket, known as the "fire arrow", and primitive bombs under the Song Dynasty (960 to 1279) - new technology partly driven by aggressive neighbours like the Jin Dynasty to the north.

1200 to 1600

The Golden Age of Islam (600 to 1600 AD) rescues the advances of classical civilisations after the fall of the Roman Empire.

Firearms technology develops rapidly and Egyptian soldiers are the first to use hand cannons and other small arms at the Battle of Ain Jalut in 1260.

However, Islamic science declines from the 17th century onwards.

1415

The Battle of Agincourt marks the zenith of mediaeval longbow technology. An English army with a high proportion of archers decimates a French army five to 10 times larger.

See The longbow's deadly secrets

1368 to 1644

China's Ming Dynasty drives firearms technology forwards. Developments include the matchlock, which eliminates the need to fire a gun with a hand-held match; the musket; and the naval mine. The dynasty's new technologies are eventually collected in the Huolongjing&colon; a treatise on warfare by Jiao Yu and Liu Ji.

1750 to 1800s

Rockets become a permanent fixture on the battlefield, having gone in and out of fashion over the centuries

Indian Sultan Fateh Ali Tippu successfully deploys rocket artillery against the British, leading inventor Sir William Congreve to develop his own version, the Congreve rocket.

1775

The first submarine used in battle, Turtle, is created by American David Bushnell. The technology remains crude and unsafe for many decades, though several subs are used in the American Civil War (1861 to 1865).

1803

The British army begins using shrapnel shells (invented earlier by the Chinese), named for their inventor Henry Shrapnel. They contain a large number of bullets released at high velocities on detonation. They are eventually replaced by high-explosive shells during the first world war.

1836

American inventor Samuel Colt patents a "revolving gun", which improves on several previous designs. Soon renamed the revolver, it is faster to reload than any other firearm, and remains popular today.

1851 to 1861

The first machine guns appear. The Belgian army's multiple-barrelled mitrailleuse is soon followed by the Gatling gun - the first gun that can be continuously fired.

1862

The USS Monitor, the first iron-clad warship, launches from New York.

It is designed by Swedish engineer John Ericsson, who had come close to beating steam locomotive Stephenson's Rocket in the competition that made it famous. Ericsson subsequently spends many years experimenting with solar power.

1876 to 1883

Schoolteacher John Holland builds the Fenian Ram, a military submarine, for a band of Irish rebels in the US.

Unlike any previous submarine it has a streamlined shape. However, the rebels are unreliable employers and Holland leaves them in disgust. The sub is never used in anger.

1884

Hiram Stevens Maxim produces the first fully automatic machine gun&colon; the Maxim gun.

In later life, crippled by bronchitis, he develops an early inhaler.

1893

After the assassination of Chicago's mayor, local priest Casimir Zeglen makes the first bulletproof vest that did away with heavy plates of metal. It is made largely from woven silk and works, but still fails to take off.

1909

Hiram Stevens Maxim's son, Hiram Percy Maxim, obtains a patent for a gun silencer.

1914

During the first world war, the British army introduces the first tanks.

1942

The Manhattan Project, the United States' attempt to build the first nuclear bomb, begins under the direction of J. Robert Oppenheimer.

1945

The first successful test of a nuclear bomb is carried out in New Mexico, on 16 July.

On 6 and 9 August, bombs are dropped on the Japanese cities of Hiroshima and Nagasaki, effectively ending the second world war and ushering in a new age of nuclear weaponry.

1952

The first fusion, or hydrogen, bomb is tested by the US in the Marshall Islands.

They use X-rays from a nuclear fission explosion to trigger nuclear fusion reactions between atoms of the hydrogen isotope tritium, like those that take place inside the sun.

A single warhead can be thousands of times more powerful than the Hiroshima bomb.

1953

The first maser (Microwave Amplification by Stimulated Emission of Radiation) is built at Columbia University. It produces a tight beam of microwaves. Originally hailed as a "ray gun", it proves impractical as a weapon.

1960

The laser (Light Amplification by Stimulated Emission of Radiation) is demonstrated for the first time. It produces a beam of red light.

Lasers find a myriad of uses in society, and in warfare are used for targeting of missiles and other weapons, and as an alternative to radar. Various prototype laser weapons are under development.

1960 to 2000

The Soviet Union begins developing a supercavitating torpedo in the 1960s. By exploiting the way water forms bubbles around fast-moving objects the Shkval can travel at 500 kilometres an hour. It is only completed in the early 1990s.

The US develop their own in 1997 and 10 years later start working on carrying humans in a supercavitation craft.

1974

The first Taser is built after five years of work by NASA researcher Jack Cover.

Billed as a non-lethal weapon, the electric stun gun is now used by police forces around the world. However, claims have been made that it is frequently abused and may cause lasting harm.

1997

The US carries out its first test of an anti-satellite laser.

1999

Experiments with radioactive hafnium are used to argue it is possible to make a simple device that releases a massive amount of gamma rays comparable to a nuclear bomb. No definitive evidence to back up the theory has been released, despite millions of dollars invested by the US military.

2001

US president George W Bush proposes a national missile defence shield. The scheme meets with stinging criticism and the technology repeatedly fails to deliver in tests.

The Active Denial System, a directed-energy weapon intended to harmlessly drive people away, is tested by the US government. The device uses a microwave beam to produce a sensation of intense heat, forcing people to move away. Despite concerns about safety, portable versions have been mooted for police.

2002

For the first time, a high-energy laser is used to shoot down artillery fire.

The Pulsed Energy Projectile (PEP), a laser that can knock you off your feet, is developed.

2007

Australian weapons company Metal Storm files a key patent for its gun, which fires a million rounds a minute.

2008

In another milestone for high-energy lasers, the Airborne Laser is fired from an aircraft for the first time.

Also, Stellar Photonics begins testing of their experimental Plasma Acoustic Shield System, which generates a dazzling series of mid-air explosions by blasting balls of plasma with high-powered lasers.

2009

A US government report advocates using neuroscience to enhance soldiers' abilities.

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Explore the history of war and weapons with our timeline of weapons technology. Please note, many of the technologies are difficult to attribute, and historical dates are often approximate. The earliest evidence of humans using spears, in a part of Germany now near Schöningen (Nature, DOI: 10.1038/385807a0).

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How much sleep do you get each night during the school year?

Are you rested in the morning before school? If so, why? If not, why not? And if not, what do you think could be done to ensure you get more sleep during the school year?

In " The Economic Case for Letting Teenagers Sleep a Little Later," Aaron E. Carroll writes:

Many high-school-age children across the United States now find themselves waking up much earlier than they'd prefer as they return to school. They set their alarms, and their parents force them out of bed in the morning, convinced that this is a necessary part of youth and good preparation for the rest of their lives.

It's not. It's arbitrary, forced on them against their nature, and a poor economic decision as well.

The National Heart, Lung and Blood Institute recommends that teenagers get between nine and 10 hours of sleep. Most in the United States don't. It's not their fault.

My oldest child, Jacob, is in 10th grade. He plays on the junior varsity tennis team, but his life isn't consumed by too many extracurricular activities. He's a hard worker, and he spends a fair amount of time each evening doing homework. I think most nights he's probably asleep by 10 or 10:30.

His school bus picks him up at 6:40 a.m. To catch it, he needs to wake up not long after 6. Nine hours of sleep is a pipe dream, let alone 10.

There's an argument to be made that we should cut back on his activities or make him go to bed earlier so that he gets more sleep. Teens aren't wired for that, though. They want to go to bed later and sleep later. It's not the activities that prevent them from getting enough sleep - it's the school start times that require them to wake up so early. More than 90 percent of high schools and more than 80 percent of middle schools start before 8:30 a.m.

Some argue that delaying school start times would just cause teenagers to stay up later. Research doesn't support that idea. A systematic review published a year ago examined how school start delays affect students' sleep and other outcomes. Six studies, two of which were randomized controlled trials, showed that delaying the start of school from 25 to 60 minutes corresponded with increased sleep time of 25 to 77 minutes per week night. In other words, when students were allowed to sleep later in the morning, they still went to bed at the same time, and got more sleep.

Students: Read the entire article, then tell us:

- Should school start times be adjusted so teenagers can get more sleep in the morning? Why or why not?

- How would a later start time personally affect you?

- Do you agree with the author that a later start time for the school day would save money and increase student success? If so, how? If not, why not?

- What other benefits, or disadvantages, can you see in delaying school start times?
Students 13 and older are invited to comment. All comments are moderated by the Learning Network staff, but please keep in mind that once your comment is accepted, it will be made public.

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Would a Later School Start Time Increase Student Success? (Published 2017)

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How much sleep do you get each night during the school year? Are you rested in the morning before school? If so, why? If not, why not? And if not, what do you think could be done to ensure you get more sleep during the school year?

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How would you react if we discovered alien life_