The earliest use of copper was probably for jewelry, ornaments, and tools. The first copper used by humans was native copper found in the metallic state and hammered into the desired shape. The tool or jewelry item could then be polished. It is believed that copper was valuable to the earliest human users because they found its physical properties interesting and unusual. It was much denser than any other material known and it could be highly polished to reflect light. Later, its useful properties were valued as well. A copper tool, though soft, was not brittle and could be hammered back into shape whereas a stone tool would shatter and be ruined. Later, it was discovered that hammering the copper object hardened it. Hammering it too much would make it brittle but heating it in a fire would make it soft and malleable again.

The earliest evidence that humans knew how to alloy copper with tin to create bronze was discovered in Thailand. It was previously thought that the earliest bronze working occurred in the Middle East around 3000 B. C. until archaeological evidence from Thailand pushed the date back much further. Only small amounts of bronze were made until the importation of tin from Cornwall began in the Second Millennium B. C.

Iron beads were found at two 6000 year old sites in Egypt along the Nile. Early iron objects were made from meteorite iron, which was found in smaller pieces and cold worked into shape, if they didn't break in the process. In Canada and Mexico, larger meteorites have been found with evidence that early Americans used stone or bronze tools to chip off a flake of iron, which was then attached to a bone or wooden handle for use as a tool.

The chronology of the human use of iron and steel is not clearly defined and is the subject of much scholarly inquiry and research. Developments occurred in different places at different times. The technological challenges in smelting iron ore were much greater than those encountered in reducing copper ores. The much higher heat of 3650 degrees Fahrenheit required could only be obtained using a charcoal fire with forced air. The furnace and the end of the blowpipe had to be made of refractory clay that could stand the extreme heat. Also, the iron could not be exposed to oxygen in the process. The oxygen had to be forced through the fire in such a way that carbon monoxide was produced. It was the hot carbon monoxide that was able to steal away the oxygen atoms so tenaciously held by the iron oxide in the ore, but if any oxygen from the air blast crept through, the iron would just re - oxidize. Even after it was smelted, the resulting bloom was not very useful as it was. It had to be re - heated and hammered to remove silica slag and other impurities. After these impurities were removed, the iron was still not pure. The early iron worker did not know whether he had iron, steel, or a brittle, useless product which contained too much carbon. To put the technological problem into perspective, the early ironsmiths didn't even know what steel was, much less whether they had produced it. Since early iron production required great quantities of carbon in the form of charcoal. the odds were good that what he wound up with was in fact, steel. If he were lucky, this was mild steel that could be easily worked and would come out of the process soft enough to be hammered into a weapon, piece of armor, or tool. later, armorers in Europe and Japan developed certain secret and often ritualistic techniques for perfecting the weapons they made from this steel. These included folding and hammering it many times over a charcoal fire and executing a condemned prisoner with the blade after heating it to the right color (a closely guarded secret). These techniques were discovered, lost, and rediscovered countless times throughout history because the smiths and the warriors who hired them desired the techniques to be kept a closely guarded secret. They were in fact carburizing and heat treating their steel products, though they had no real knowledge of chemistry. It was only in the Nineteenth Century A. D. that metalsmiths really began to understand the physics and chemistry of what they were doing.

A series of bas reliefs carved on the wall of a temple in Thebes shows Pharaoh Ramses III defeating an attempt to invade Egypt by land and by sea simultaneously. The reliefs clearly shows flights of arrows shot by the Egyptian archers. The carvings also show that warfare at sea was a hand - to - hand affair, much like combat between land armies. The tactic of ramming, in which combat was between the ships themselves, did not develop for another three hundred years.

The Battle of Lepanto, fought between the Turkish fleet of Sultan Selim II and the allied Christian fleet was the last time two large fleets slugged it out in oared galleys rowed by human power. The Christian fleet, consisting of contingents from Spain, the Papal States, Venice, and Genoa and commanded by Don Juan of Austria totally demolished the Turkish fleet under Ali Pasha and the Corsair leader Ochialli. From this time on, major sea battles would be fought between sailing vessels up until the age of steam.

In 1777, The submarine Turtle was built by American inventor John Bushnell and operated by Sergeant Ezra Lee. It carried an explosive device designed to blow a hole in the hull of an enemy ship. Bushnell had attached an auger to the Turtle which was operated by a crank from the inside. The idea was to drill a hole in the enemy hull and attach the bomb, which would be given a long enough fuse to allow the little sub to get away safely. The bomb worked fine on its first trial, scaring the crew of the British frigate Eagle out of their wits. The auger and drill did not, however, and the bomb exploded noisily but harmlessly on the surface. The frigate's copper sheathed bottom, intended to protect the ship from teredo worms, was too hard for the drill to penetrate.

Between May 4th and 7th, the Battle of the Coral Sea was fought between a Japanese and an American task group which were completely out of visual range of each other. The entire battle was fought by aircraft attacking the opposing fleet. No shots were exchanged between surface ships signified that the era of the Dreadnought as the most powerful naval weapon was over.

In August of 1945, the two Japanese cities of Hiroshima and Nagasaki were destroyed by atomic bombs dropped from American B-29 bombers. While earlier fire bombings may have caused greater destruction from a single raid over the course of several hours, these new weapons performed their devastation at a single stroke.