The British Sten Machinegun was a simple and inexpensive machinegun built by the british during WWII. The British army started WWII with many high quality weapons but lacked a submachinegun. This was quickly realised to be a problem and so they started by buying Thompson submachineguns from america. However Thompson's had to come accross the atlantic and were EXPENSIVE. The british needed something cheaper. So they looked around and eventually decided to make copies of the german WWI MP18. Then after a bunch of tinkering they figured out how to make them CHEAP. Millions of sten guns were made by the end of the war. The Sten MK V was one of the final iterations with a little more refinement. They were used heavily in late war actions such as Operation Market Garden. They are not precision instruments but they are simple, easy to shoot, mostly reliable, and have tons of historical value.