A currency is an asset type that can be traded. Currencies are traded in pairs and some of the most common examples of these are: USD/GBP, USD/EUR, USD/CAD and many more. The basic currency transaction is comprised of two currencies involved in a currency change – one being sold, the other being purchased. A currency pair’s value is measured by the base currency (the first one quoted) divided by the quote currency (the second), denoting how much of the latter is valued against a single unit of the former.
Commodities refer to basic goods usually used as inputs in the manufacture of products or provision of services. The most common traded commodities are gold, silver and oil.
A stock refers to the stock of a specific company which is available to trade on the financial stock market. Some examples include: Apple Inc, Facebook, BP, Barclays and Vodafone.
The aggregate value of a group of selected stocks; the index is used to describe its market and compare returns on investment. Some of the most popular indices include the Dow Jones Industrial Average, NASDAQ Composite, S&P 500, and FTSE 100.