Kalashnikov Automatic Rifle

Small-arms designer Mikhail Kalashnikov created this weapon in 1947, the Avtomat Kalashnikov (Автомат Калашникова), thus the AK-47.

History's most popular weapon of war, the AK's an avatar of revolutionary movement across the Third World. If you've been watching, they're everywhere in Ukraine. Seems like everyone's totin' one, even civilians. 

More, from Phillip Killicoat, "Weaponomics: The Global Market for Assault Rifles":

Existing data on aspects of the small arms market are extremely limited. Since 2001, the In the case of small arms there isan obvious choice: the AK-47 assault rifle. Of the estimated 500 million firearms worldwide, 100 million belong to the Kalashnikov family, three-quarters of which are AK47s (Small Arms Survey 2004). The pervasiveness of this may be explained in large part by its simplicity. The AK-47 was initially designed for ease of operation and repair by glove-wearing Soviet soldiers in arctic conditions. Its breathtaking simplicity means that it can also be operated by child soldiers in the African desert. Kalashnikovs are a weapon of choice for armed forces and non-state actors alike. They are to be found in the arsenals of armed and special forces of more than 80 countries. In practically every theatre of insurgency or guerrilla combat a Kalashnikov will be found. The popularity of the AK-47 is accentuated by the view that it was a necessary tool to remove colonial rulers in Africa and Asia. Indeed, an image of the rifle appears on the Mozambique national flag, and “Kalash”, an abbreviation of Kalashnikov, is a common boy’s name in some African countries.

The AK-47’s popularity is generally attributed to its functional characteristics; ease of operation, robustness to mistreatment and negligible failure rate. The weapon’s weaknesses - it is considerably less accurate, less safe for users, and has a smaller range than equivalently calibrated weapons - are usually overlooked, or considered to be less important than the benefits of its simplicity. But other assault rifles are approximately as simple to manage, yet they have not experienced the soaring popularity of the Kalashnikov.

The AK-47’s ubiquity could alternatively be explained as a result of a path dependent process. Economic historians recognize that an inferior product may persist when a small but early advantage becomes large over time and builds up a legacy that makes switching costly (David 1975). In the case of the AK-47 that early advantage may be that as a Soviet invention it was not subject to patent and so could be freely copied. Furthermore, large caches of these weapons were freely distributed to regimes and rebels sympathetic to the Soviet Union - more freely, that is, than weapons were distributed by the US - thereby giving the AK-47 a foothold advantage in the emerging post-World War II market for small arms.

According to a path dependence interpretation, inferior durable capital equipment may remain in use because the fixed costs are already sunk, while variable costs (e.g. ammunition, learning costs for new recruits) are lower than the total costs of replacing Kalashnikovs with a new generation of weapons of apparently superior quality. Whatever the exact causes, it remains that for the last half-century the AK-47 has enjoyed a near dominant role in the market for assault rifles making it the most persistent piece of modern military technology. Since the technology used in the AK-47 is essentially unchanged from the original, one may be confident that the prices observed across time and countries are determined market conditions rather than changes in the product...

SOURCE: Foreign Policy, "Looking for a deal on AK-47s? Go to Africa."