What is Sniper and what are its important in war

A sniper is a marksman or qualified specialist who operates alone, in a pair, or with a sniper team to maintain close visual contact with the enemy and engage targets from concealed positions or distances exceeding the detection capabilities of enemy personnel. Snipers typically have highly selective or specialized training and use crew-served high-precision/special application rifles and optics, and often have sophisticated communication assets to feed valuable combat information back to their units or military bases.

Most sniper teams operate independently, with little combat asset support from their parent units; their job is to deliver discriminatory, highly accurate rifle fire against enemy targets that cannot be engaged successfully by the regular rifleman because of range, size, location, fleeting nature, or visibility. Sniping requires the development of basic infantry skills to a high degree of skill. A sniper's training incorporates a wide variety of subjects designed to increase value as a force multiplier and to ensure battlefield survival. The art of sniping requires learning and repetitively practicing these skills until mastered. A sniper must be highly trained in long range rifle marksmanship and field craft skills to ensure maximum effective engagements with minimum risk.
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Different countries use different military doctrines regarding snipers in military units, settings, and tactics.

Generally, a sniper's primary function in modern warfare is to provide detailed reconnaissance from a concealed position and, if necessary, to reduce the enemy's fighting ability by neutralizing high-value targets (especially officers and other key personnel) and in the process pinning down and demoralizing the enemy.[7][8] Typical sniper missions include managing intelligence information they gather during reconnaissance and surveillance, target acquisition for air-strikes and artillery, assist employed combat force with fire support and counter-sniper tactics, killing enemy commanders, selecting targets of opportunity, and even destruction of military equipment, which tend to require use of anti-materiel rifles in the larger calibers such as the .50 BMG, like the Barrett M82, McMillan Tac-50, and Denel NTW-20.[8]

Soviet and Russian derived military doctrines include squad-level snipers. Snipers have increasingly been demonstrated as useful by US and UK forces in the recent Iraq campaign in a fire support role to cover the movement of infantry, especially in urban areas.[8]

Military snipers from the US, UK, and other countries that adopt their military doctrine are typically deployed in two-man sniper teams consisting of a shooter and spotter.[9] A common practice is for a shooter and a spotter to take turns in order to avoid eye fatigue.[8] In most recent combat operations occurring in large densely populated towns, such as Fallujah, Iraq, two teams would be deployed together to increase their security and effectiveness in an urban environment. A sniper team would be armed with their long range weapon, and a shorter ranged weapon to engage and protect the team should enemies come in close contact. German doctrine of largely independent snipers and emphasis on concealment developed during the Second World War have been most influential on modern sniper tactics, currently used throughout Western militaries (examples are specialized camouflage clothing, concealment in terrain and emphasis on coup d'œil).

The Whitworth rifle was arguably the first long-range sniper rifle in the world.[28] Designed by Sir Joseph Whitworth, a prominent British engineer, it used polygonal rifling instead, which meant that the projectile did not have to bite into grooves as was done with conventional rifling. His rifle was far more accurate than the Pattern 1853 Enfield, which had shown some weaknesses during the recent Crimean War. At trials in 1857 which tested the accuracy and range of both weapons, Whitworth's design outperformed the Enfield at a rate of about three to one. The Whitworth rifle was capable of hitting the target at a range of 2,000 yards, whereas the Enfield could only manage it at 1,400 yards.[29]

During the Crimean War, the first optical sights were designed to fit onto rifles. Much of this pioneering work was the brainchild of Colonel D. Davidson, using optical sights produced by Chance Brothers of Birmingham. This allowed a marksman to observe and target objects more accurately at a greater distance than ever before.[30] The telescopic sight, or scope, was originally fixed and could not be adjusted, which therefore limited its range.

Despite its success at the trials, the rifle was not adopted by the British Army. However, the Whitworth Rifle Company was able to sell the weapon to the French army, and also to the Confederacy during the American Civil War.[31] Both the Union and Confederate armies employed sharpshooters. The most notable incident was during the Battle of Spotsylvania Court House, where on 9 May 1864, Union General John Sedgwick was killed at a range of about 1,000 yards (910 meters) after saying the enemy "couldn't hit an elephant at this distance."[32][33][34][35]