Bottle caps, also referred to as caps for short, are the main currency of the Fallout series.
Background and History Edit
In the Core Region, the relative scarcity of bottle caps made them a perfect currency for Hub merchants to adopt in the 22nd century, leading to the nickname "Hubbucks" and "Hubscript." Backed by the value of water, the Hub merchants supported bottle caps because the technology to manufacture them and paint their surfaces had been mostly lost in the Great War, which limited any counterfeiting efforts. Secondly, there are a limited number of bottle caps, which preserve their value against inflation to some degree. For similar reasons the East Coast merchants also recognize bottle caps as a currency, although who backs them and guarantees their value is unknown.
While becoming the standard currency for Hub merchants in the 22nd century, by the mid-23rd century bottle caps were replaced by New California Republic (NCR) dollars, which were backed by gold. Caps would once again become a regularly-used currency after the destruction of NCR's gold reserves by the Brotherhood of Steel destabilized the value of the dollar.
By the late-23rd century, the NCR's tenuous grip on the Core Region, the presence of Caesar's Legion (who have their own currency), and the low value of the now water-backed NCR dollar caused bottle caps to re-emerge as the standard currency of the Mojave Wasteland in 2281. Nevertheless, NCR and Legion currency are both considered legal tender by the various caravan companies and on the New Vegas Strip. Mojave merchants also accept nonstandard variants, such as Sunset Sarsaparilla bottle caps.
However, based on the relative prices of items on the East Coast and West Coast, the bottle cap currency is used in larger amounts in the former.