A letter of credit (LC), also known as a documentary credit or bankers commercial credit, or letter of undertaking (LoU), is a payment mechanism used in international trade to provide an economic guarantee from a creditworthy bank to an exporter of goods. Letters of credit are used extensively in the financing of international trade, when the reliability of contracting parties cannot be readily and easily determined. Its economic effect is to introduce a bank as an underwriter that assumes the counterparty risk of the buyer paying the seller for goods. History The letter of credit has been used in Europe since ancient times. Letters of credit were traditionally governed by internationally recognized rules and procedures rather than by national law. The International Chamber of Commerce oversaw the preparation of the first Uniform Customs and Practice for Documentary Credits (UCP) in 1933, creating a voluntary framework for commercial banks to apply to transactions worldwide. In the late 19th century and early 20th century, travelers commonly carried a circular letter of credit issued by a relationship bank, which allowed the beneficiary to withdraw cash from other banks along their journey. This type of letter of credit was eventually replaced by traveler's checks, credit cards and automated teller machines. Although letters of credit first existed only as paper documents, they were regularly issued by telegraph in the late 19th century, and by telex in the latter half of the 20th century. Beginning in 1973 with the creation of SWIFT, banks began to migrate to electronic data interchange as a means of controlling costs, and in 1983 the UCP was amended to allow "teletransmission" of letters of credit. By the 21st century, the vast majority of LCs were issued in electronic form and entirely "paperless" LCs were becoming more common. Marcell David Reich (commonly known as Marc Rich) popularised the use of letters of credit in the oil trade. Terminology UCP 600 (2007 Revision) regulates common market practice within the letter of credit market. It defines a number of terms related to letters of credit which categorise the various factors within any given transaction. These are crucial to understanding the role financial institutions play within. These include: The Applicant is the person or company who has requested the letter of credit to be issued; this will normally be the buyer. The Beneficiary is the person or company who will be paid under the letter