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Digital assets and currencies

Understand assets, networks and trading mechanics with sources you can check.

Trading basics

Tuvaluan dollar

The Tuvaluan dollar is one of the currencies of Tuvalu, whose unofficial international currency code is TVD. Tuvalu has never had banknotes of its own, and has been issuing coins since 1976. However, the Tuvaluan dollar is used as a unit of account, and is pegged to the Australian dollar (the other currency of Tuvalu) at parity. From 1966 to 1976, Tuvalu officially used the Australian do

Finance

Twin crises

In economics, twin crises, also called a balance of payments crisis, are simultaneous crises in banking and currency. The term was introduced in the late 1990s by economists Graciela Kaminsky and Carmen Reinhart after several such crises worldwide.

Fiat currencies

U.S. Dollar Index

The U.S. Dollar Index (USDX, DXY, DX, or, informally, the "Dixie") is an index (or measure) of the value of the United States dollar relative to a basket of foreign currencies, often referred to as a basket of U.S. trade partners' currencies. The Index goes up when the U.S. dollar gains "strength" (value) when compared to other currencies.

Finance

U.S. Strategic Bitcoin Reserve

The Strategic Bitcoin Reserve is a proposed reserve asset, funded by the United States Department of the Treasury's forfeited bitcoin, announced by United States president Donald Trump in March 2025. The creation of the United States Digital Asset Stockpile for non-bitcoin assets was also announced. Trump has previously stated that he wants the United States to become the "crypto capita

Trading basics

UAE Exchange

UAE Exchange (Arabic: مركز الإمارات العربية المتحدة للصرافة; Markaz Al'Imarat Alearabiat Almutahidat Lilsarafa) was a United Arab Emirates-based company dealing primarily in remittance, foreign exchange and bill payment services.

Banking

UnionPay

UnionPay (Chinese: 银联; pinyin: Yínlián), also known as China UnionPay (Chinese: 中国银联; pinyin: Zhōngguó Yínlián) or by its abbreviation, CUP or UPI internationally, is a Chinese state-owned financial services corporation headquartered in Shanghai, China. It provides bank card services and a major card scheme in mainland China. Founded on 26 March 2002, China UnionPay is an association fo

Finance

United Kingdom insolvency law

United Kingdom insolvency law regulates companies in the United Kingdom which are unable to repay their debts. While UK bankruptcy law concerns the rules for natural persons, the term insolvency is generally used for companies formed under the Companies Act 2006. Insolvency means being unable to pay debts. Since the Cork Report of 1982, the modern policy of UK insolvency law has been to

Fiat currencies

United States dollar

The United States dollar (symbol: $; currency code: USD) is the official currency of the United States (U.S.) and several other countries. The U.S. Coinage Act of 1792 established the dollar as the base unit, with each dollar divided into 100 cents (symbol: ¢). U.S. banknotes are issued in the form of Federal Reserve Notes, popularly called greenbacks due to their predominantly green col

Trading basics

Unsecured debt

In finance, unsecured debt refers to any type of debt or general obligation that is not protected by a guarantor, or collateralized by a lien on specific assets of the borrower in the case of a bankruptcy or liquidation or failure to meet the terms for repayment. Unsecured debts are sometimes called signature debt or personal loans. These differ from secured debt such as a mortgage, whic

Assets

Unspent transaction output

In cryptocurrencies, an unspent transaction output (UTXO, often capitalized as UTxO) is a distinctive element in a subset of digital currency models. A UTXO represents a certain amount of cryptocurrency that has been authorized by a sender and is available to be spent by a recipient. The utilization of UTXOs in transaction processes is a key feature of many cryptocurrencies, but it prima

Securities & exchanges

Uptick rule

The uptick rule is a trading restriction that states that short selling a stock is allowed only on an uptick. For the rule to be satisfied, the short must be either at a price above the last traded price of the security, or at the last traded price when the most recent movement between traded prices was upward (i.e. the security has traded below the last-traded price more recently than a

Fiat currencies

USD: Difference Between Fiat Currency and On-Chain Assets

The international currency code for the US dollar is USD. This article covers its definition, mechanisms, verification methods, and common misconceptions.

Stablecoins

USDT: Tether and Network Selection

USDT is a US dollar-denominated stablecoin issued by Tether, designed to maintain a close value relationship with the US dollar. This article introduces its positioning, mechanism, verification checklist, and common misconceptions.

Securities & exchanges

Vanna–Volga pricing

The Vanna–Volga method is a mathematical tool used in finance. It is a technique for pricing first-generation exotic options in foreign exchange market (FX) derivatives.

Trading basics

Venture capital trust

A venture capital trust or VCT is a tax efficient UK closed-end collective investment scheme designed to provide venture capital for small expanding companies, and income (in the form of dividend distributions) and/or capital gains for investors. VCTs are a form of publicly traded private equity, comparable to investment trusts in the UK or business development companies in the United St

Payments & settlement

Vipps

Vipps is a Norwegian mobile payment application designed for smartphones originally developed by DNB. Vipps was released May 30, 2015 and, having reached 1 million users by November 5, 2015, Vipps became Norway's largest payment application. Although Vipps was developed by DNB, customers of any Norwegian bank can use it. Vipps is a member of the European Mobile Payment Systems Associatio

Payments & settlement

Virtual goods

Virtual goods are non-physical objects and money purchased for use in online communities or online games. Digital goods, on the other hand, may be a broader category including digital books, music, and movies. Virtual goods are a subclass of intangible goods.

Trading basics

Vix Technology

Vix Technology (Vix) is an Australian company that designs, supplies and operates automated fare collection (AFC) systems, intelligent transportation systems (ITS), access, payment and passenger information display systems (PIDS) for the public transit industry.

Payments & settlement

Vocalink

Vocalink is a payment systems company headquartered in the United Kingdom, created in 2007 from the merger between Voca and LINK. It designs, builds and operates the UK payments infrastructure, which underpins the provision of the Bacs payment system and the UK ATM LINK switching platform covering 65,000 ATMs and the UK Faster Payments systems.

Assets

Voiceverse NFT plagiarism scandal

In January 2022, 15—the pseudonymous Massachusetts Institute of Technology (MIT) artificial intelligence researcher and creator of the non-commercial generative artificial intelligence voice synthesis research project 15.ai—discovered that the blockchain-based technology company Voiceverse had plagiarized from their platform. Voiceverse marketed itself as a service that offered AI voice

Securities & exchanges

Volatility risk

Volatility risk

Securities & exchanges

Volfefe index

The Volfefe Index was a stock market index of volatility in market sentiment for US Treasury bonds caused by tweets by President Donald Trump.

Trading basics

Vulture fund

A vulture fund is a hedge fund or private-equity fund that invests in debt considered to be very weak or in default, known as distressed debt. Investors in the fund profit by buying debt at a discounted price on a secondary market and then using numerous methods to sell the debt for more than the purchasing price. Debtors include companies, countries, and individuals.

Fiat currencies

Wall Street Journal Dollar Index

The Wall Street Journal Dollar Index (WSJ Dollar Index) is an index (or measure) of the value of the U.S. dollar relative to 16 foreign currencies.

Securities & exchanges

Warren Buffett

Warren Edward Buffett ( BUFF-it; born August 30, 1930) is an American investor and philanthropist who is the chairman emeritus and former CEO of the conglomerate Berkshire Hathaway. As a result of his success, Buffett is one of the best-known investors in the world. According to Forbes, as of January 2026, Buffett's estimated net worth stood at US$148.9 billion, making him the ninth-rich

Trading basics

WinCapita

WinCapita, previously WinClub and GiiClub, was a Finnish Internet-based Ponzi scheme that advertised itself as a private investment club engaged in currency trading. In reality, it was a bucket shop like many other foreign exchange fraud schemes. It operated mainly in Finland, with a smaller number of members also in Sweden. The operation collected about 100 million euros from more than

Payments & settlement

WooCommerce

WooCommerce is an open-source e-commerce plugin for WordPress. It is designed for online merchants of all sizes using WordPress. Launched on September 27, 2011, the plugin gained popularity for its simplicity to install and customize and for the market position of the base product as freeware (even though many of its optional extensions are paid and proprietary). WooCommerce is developed

Finance

Working Group on Financial Markets

The President's Working Group on Financial Markets, known colloquially as the Plunge Protection Team, or "(PPT)" was created by Executive Order 12631, signed on March 18, 1988, by United States President Ronald Reagan.

Fiat currencies

World currency

A world currency, supranational currency, or global currency is a currency that is widely used in international finance or in international trade to price goods or other transactions. It is generally a currency which is stable in terms of inflation and has a high demand on the foreign exchange market. Greek and Roman coins were the first world currency, followed by Dutch guilders in the

Finance

World Liberty Financial

World Liberty Financial (WLFI) is a decentralized finance protocol developed by its namesake company. It was founded in 2024 by Zachary Folkman, Chase Herro, Alex Witkoff, Zach Witkoff, and Trump family members. It is a business venture of the Trump family. The Trump family receives 75% of net proceeds when WLFI sells tokens, as well as gets a cut of stablecoin profits. By December 2025,

Finance

World Pensions & Investments Forum

The World Pensions Forum, also called World Pensions & Investments Forum, is a research and policy oriented conference organised by M. Nicolas Firzli, founder of the World Pensions Council (WPC), in partnership with regional and supranational organisations, large public and private institutional investors from G10 countries, the emerging nations of Eastern Europe, Latin America, Asia and

Trading basics

XE.com

Xe.com (Xe) is a Canada-based online foreign exchange tools and services company headquartered in Newmarket, Ontario. It is best known for its online currency converter application that offers exchange rate information, international money transfers, and other currency-related services via its website, mobile apps, and other online channels. It has been a subsidiary of Euronet Worldwid

Fiat currencies

XTX Markets

XTX Markets Limited is a British algorithmic trading company based in London. It was founded in January 2015 by Alexander Gerko, who is currently co-CEO alongside Hans Buehler. The company employs around 300 people globally (as of 2026) and uses state-of-the-art machine learning technology to produce price forecasts for over 50,000 financial instruments across equities, fixed income, cur

Payments & settlement

Yang Cheng Tong

Yang Cheng Tong (Chinese: 羊城通; Jyutping: joeng4 sing4 tung1; pinyin: Yáng chéng tōng; lit. 'Ram City Pass') is a contactless rechargeable stored value smartcard designed for paying the travel fares in the metro, buses, taxis and ferries in Guangzhou, China, along with most other cities in Guangdong, with the exception of Shenzhen. It was developed and managed by Guangzhou Yang Cheng Tong

Trading basics

ZuluTrade

ZuluTrade is a Greek financial technology company that operates an online and mobile social and copy trading platform. The platform allows users to automatically copy the trades of other investors in the foreign exchange market. As of 2014 ZuluTrade had around one million users and an executed trading volume of over $800 billion.