Short answers, pulled from the story.
The earliest unambiguous weapons found by archaeologists are the Schöningen spears, eight wooden throwing spears dating back more than 300,000 years. These artifacts were discovered in Germany and provide physical proof that early hominids were capable of complex hunting strategies and organized violence.
The development of metal tools began with copper during the Copper Age about 3,300 BC and was followed by the Bronze Age. This era led to the creation of the Bronze Age sword and similar weapons that were sharper, stronger, and more durable than their stone or wooden predecessors.
The introduction of gunpowder from Asia at the end of the post-classical period revolutionized warfare by marking the beginning of a new era in military technology. This innovation led to the development of firearms that released energy from combustible propellants rather than from a counterweight or spring.
World War I marked the entry of fully industrialized warfare as well as weapons of mass destruction such as chemical and biological weapons. The technological escalation included the wide introduction of aircraft into warfare and naval warfare with the introduction of aircraft carriers.
According to research institute SIPRI, the volume of international transfers of major weapons in 2010 to 2014 was 16 percent higher than in 2005 to 2009. The arms sales of the world's 100 largest private arms-producing and military services companies totaled 420 billion dollars in 2018.
Every year landmines kill 15,000 to 20,000 people and severely maim countless more. Unexploded ordnance are bombs, land mines, naval mines, and similar devices that did not explode when they were employed and still pose a risk for many years or decades.