Israeli Military Industries Tavor Assault Rifle- 21st Century, also known simply as the Tavor.
Designed to replace M16 and M4 rifles and carbines, the Tavor is chambered in 5.56NATO and is compatible with STANAG AR-15 magazines and all NATO 5.56 cartridges.
The Israel Defense Forces decided that they were unhappy with the overall performance and characteristics of the M4, especially its high rate of stoppages and overall length. They began a lengthy process to design a new rifle that would be much more reliable with a shorter overall length, while retaining some of the positive features of the AR-15 series.
The TAR 21 is a bull pup-style assault rifle, meaning that the operating group and magazine are located behind the firing hand, decreasing the overall length of the weapon while not reducing the barrel length. This makes the Tavor much easier to use in urban areas (such as Gaza) and when exiting vehicles than longer weapons. The Tavor was also designed with a red dot sight and a IR/visible laser aiming module built into the weapon. It also has a fold-up iron sight.
The ambidextrous safety/selector has a semi auto, burst, and fully automatic mode and the optic powers off when the safety is on. The end result shows that the Tavor is a very accurate and reliable weapon and in addition to the IDF it has been adopted by several Special Forces and SWAT units worldwide, including India, Turkey, Georgia, and Portugal, with more units and Countries likely to adopt in in the future.
The Tavor is offered in 4 variants:
T.A.R. 21--Basic Carbine
G.T.A.R. 21-- Notched barrel version for attaching a 40mm grenade launcher such as the M203
C.T.A.R. 21-- Compact version for Special Forces
S.T.A.R. 21-- Sharpshooter's version with a bi pod and magnified optic scope
Civilian-legal semi automatic versions of the Tavor are being made, although I have yet to see one for sale, and I imagine they will be quite pricey, likely over $2,000. Oh well.
For purposes of comparison, look at this TAR 21 and a SIG 556. As you can see the Tavor is much shorter than this SIG and yet retains the accuracy of a longer weapon.