Acronym for National Association of Securities Dealers Automated Quotations, the NASDAQ is an American stock market focused primarily on technology companies. Founded in 1971, it is now one of the main barometers of the technology industry and the global digital economy. One of the most famous indices of this financial centre is the Nasdaq Composite and the Nasdaq 100. The Nasdaq Composite is one of the most closely followed stock market indices in the world. It comprises more than 3,000 companies listed on the Nasdaq, ranging from technology giants to small start-ups. The Nasdaq 100 is a subset of the Nasdaq Composite, comprising the 100 largest non-financial companies listed on the Nasdaq. This index includes leading companies in fields such as technology, biotechnology and retail. But in addition to these two flagship indices, the NASDAQ financial centre has several stock market indices calculated on the basis of the market capitalisation of the companies that make them up. Unlike the Dow Jones indices, companies with a larger market capitalisation therefore have a greater impact on the index. Over the years, the Nasdaq indices have evolved to reflect changes in the economy and technology. The inclusion or exclusion of companies in the indices is a process that closely follows trends in the new technology market. Because of this thematic focus, Nasdaq indices are often more volatile than other major indices such as the Dow Jones Industrial Average or the S&P 500.