Sniper (snip•er): n.          1.) A skilled military shooter detailed to spot and pick off enemy soldiers from a concealed place.          2.) One who shoots at other people from a concealed place.
The word sniper originates from the snipe bird. These birds are so small and quick that snipe hunters (or, snipers) had to be extremely stealthy as well as expert marksmen. The sniper has evolved from a hunter using a black-powder rifle to the modern sniper (sometimes called sharpshooter) who has access to rifles that are adequately accurate at distances of more than a mile.
The Speckled Winter Snipe
Sniper Rifles
	The work of beauty at left is the Heckler & Koch PSG-1 Sniper Rifle. This rifle is popular with many Special Ops groups and anti-terrorist organizations. It is not widely used in military applications because (1) it ejects the shells approximately 10 meters away, which can give away a sniper's position, and (2) it can only be fitted with the Hensold 6x42 scope. No other scope can be used, unless you want to try grinding off the mounts and welding on your own stuff. It's not a widely-used rifle due to its hefty price tag of around nine thousand dollars ($9,325 last I checked). It fires the 7.62 x 51mm NATO cartridge (.308 Winchester). Every PSG-1 manufactured must pass an extensive accuracy test of 50 shots into an 80mm (3.14") circle at three hundred meters. Keep in mind that this is 50 shots, not a three-round group. The overall length of the PSG-1 is 47.56"(120.8 cm) and it weighs in at 17.81 pounds (8.10kg), which is pretty heavy. The stock has an adjustable butt plate as well as an adjustable cheek plate. The gun comes fitted with the Hensold 6x42 scope, which, as I stated above, is not interchangeable. All in all, however, if it's pinpoint accuracy you're looking for, and money is no object, the PSG-1 is what you want.
	This is the SVD (Snayperskaya Vintovka Dragunova) Dragunov. It's (obviously, from the title) a Russian rifle. It was the first rifle designed from scratch with sniping in mind. It was introduced into the Soviet army in the 1950s. It uses the Russian 7.62x54mm cartridge in a 10-rd. detachable box magazine. The rifle is deadly out to about 600m, after that it takes a lot more concentration to hit anything consistently. It really can't stand up to today's rifles, but it performs extremely well for what it was designed for. Thanks to SniperCentral for the info.
Other Equipment
	This is a night vision rifle scope. More specifically, it is the Dedal 140 Pro night vision scope. The tube mounted on top of the scope itself is the IR (infra-red) illuminator. This is basically a flashlight that shines in the infra-red spectrum. There are two types of night vision: light amplification and infra-red. The Dedal 140 Pro is an IR scope. It uses the IR illuminator to shine IR light on whatever its user is looking at, and the scope picks up on that light. The sniper using it doesn't have to worry, though, because infra-red light is invisible to the naked eye. The sniper's target would have to also have an IR scope to see the illuminator. Its reticle (the "bull's-eye") is illuminated as well, and you can see what it looks like in the lower-right corner of the picture at left. This particular scope retails for $599. There are cheaper ones, however. You can find it at Night Vision Optics.com.