Shields vary greatly in size and shape, ranging from large panels that protect the user's whole body to small models (such as the buckler) that were intended for hand-to-hand-combat use.
Finally, shields vary greatly in shape, ranging in roundness to angularity, proportional length and width, symmetry and edge pattern; different shapes provide more optimal protection for infantry or cavalry, enhance portability, provide secondary uses such as ship protection or as a weapon and so on.
In prehistory and during the era of the earliest civilisations, shields were made of wood, animal hide, woven reeds or wicker.
In classical antiquity, the Barbarian Invasions and the Middle Ages, they were normally constructed of poplar tree, lime or another split-resistant timber, covered in some instances with a material such as leather or rawhide and often reinforced with a metal boss, rim or banding.
It was common for Aristocratic officials such and knights, barons, dukes, and kings to have their shields painted with customary designs known as a coat of arms.
In the 20th and 21st century, shields have been used by military and police units that specialize in anti-terrorist actions, hostage rescue, riot control and siege-breaking.
During the 14th–13th century BC, the Sards or Shardana, working as mercenaries for the Egyptian pharaoh Ramses II, utilized either large or small round shields against the Hittites.
[5] Examples of Germanic wooden shields circa 350 BC – 500 AD survive from weapons sacrifices in Danish bogs.
The heavily armored Roman legionaries carried large shields (scuta) that could provide far more protection, but made swift movement a little more difficult.
Famously, the Romans used their shields to create a tortoise-like formation called a testudo in which entire groups of soldiers would be enclosed in an armoured box to provide protection against missiles.
This was done to accommodate the shaft of a spear, thus facilitating tactics requiring the soldiers to stand close together forming a wall of shields.
Both kite and heater style shields were made of several layers of laminated wood,[6] with a gentle curve in cross section.
In the 18th century, the Scottish clans used a small, round targe that was partially effective against the firearms of the time, although it was arguably more often used against British infantry bayonets and cavalry swords in close-in fighting.
Zulu warriors carried large lightweight shields called Ishlangu made from a single ox hide supported by a wooden spine.
These typically offer protection from relatively large and low velocity projectiles, such as rocks and bottles, as well as blows from fists or clubs.
They are typically employed by specialist police, such as SWAT teams in high risk entry and siege scenarios, such as hostage rescue and breaching gang compounds, as well as in antiterrorism operations.