The Nasdaq Explained: What Every Investor Needs to Know

TL;DR： Nasdaq is a U.S. stock exchange that operates electronically and is known for its concentration of technology companies. What investors often call the “Nasdaq” actually refers to two different indices: the Nasdaq Composite, which includes more than 3,000 stocks, and the Nasdaq-100, which represents the 100 largest non-financial companies. Understanding the difference between the two helps you track global tech-stock trends more clearly.

When global investors talk about tech stocks, Nasdaq almost inevitably comes up. For many Hong Kong investors, “Nasdaq” is one of the most frequently encountered terms when investing in U.S. equities—yet they may not be entirely sure what it really means. Is Nasdaq an exchange or an index? Why is it considered a key gauge of tech stocks? Starting from the basics, this article provides a comprehensive explanation of Nasdaq’s structure, how it operates, and what it means for investors—helping you build a solid foundation of understanding.

What is Nasdaq? Start with the name

Nasdaq’s full English name is National Association of Securities Dealers Automated Quotations, which literally refers to an “automated quotation system” for the National Association of Securities Dealers. The name itself captures its core feature: replacing traditional manual quoting with an automated electronic system, positioning it from the outset as a technology-oriented, modern trading platform.

Nasdaq was officially established on February 8, 1971, as the world’s first fully electronic stock exchange. Before that, over-the-counter stock trading relied on phone-based matching, which was inefficient and lacked price transparency. Nasdaq fundamentally changed how the market worked by centralizing quotation information in computer systems, greatly improving trading speed and fairness.

How Nasdaq differs from the New York Stock Exchange

Many people confuse Nasdaq with the New York Stock Exchange (NYSE). Both are major U.S. stock exchanges, but there are several clear differences.

The NYSE has more than a century of history and traditionally features a physical trading floor, with some trades still involving human handling. By contrast, Nasdaq has operated entirely on an electronic platform since day one and has no physical trading venue. In addition, the two exchanges have different listing thresholds—historically, Nasdaq has been more flexible with emerging companies, which has attracted a large number of tech startups and high-growth firms to list there.

Nasdaq’s two core indices

When investors say “the Nasdaq rose today,” they are usually referring not to the exchange itself, but to the performance of related indices. Nasdaq has two of the most commonly cited indices, each built on a different design concept.

Nasdaq Composite Index

The Nasdaq Composite Index is the broadest measure, covering all stocks listed on the Nasdaq exchange—currently more than 3,000. It is calculated using a market-capitalization-weighted methodology, meaning larger companies have a greater impact on index performance. Because any stock listed on Nasdaq is automatically included, the Composite has very wide coverage, spanning both tech giants and smaller companies.

Nasdaq-100 Index

The Nasdaq-100 Index (NDX), created in 1985, is the “best-of” version of the Composite. It includes only the 100 largest non-financial companies listed on Nasdaq by market capitalization. Financial companies are excluded, making the index more concentrated in industry leaders across technology, consumer, biotechnology, and related sectors.

Tip： The Composite is “big and broad,” reflecting the overall direction of the entire Nasdaq market. The Nasdaq-100 is “lean and heavyweight,” focusing on the largest non-financial companies and more directly representing the performance of top-tier tech names. When referencing data, investors should pay attention to which index is being cited.

In addition, the indices impose caps on constituent weights to ensure no single stock’s influence becomes overly concentrated, allowing the index to better reflect overall sector trends rather than being dominated by one or two names.

Why is Nasdaq considered a key gauge for tech stocks?

Nasdaq is famous for tech stocks, closely tied to its historical background and listing policies. Compared with traditional exchanges, Nasdaq’s listing requirements have been more flexible, allowing many fast-growing technology companies—often not yet meeting traditional profitability thresholds—to list and raise capital.

The internet wave of the 1990s led many major tech companies to list on Nasdaq, further cementing its status as the tech exchange. To this day, many representative companies in artificial intelligence (Artificial Intelligence, or AI), cloud computing, biotechnology, and other fields continue to choose Nasdaq for their listings.

Technology-related companies have long accounted for a high proportion of the Nasdaq Composite—far exceeding sectors such as industrials, energy, or traditional financials. This structural feature makes Nasdaq indices particularly responsive in reflecting the overall health of the technology industry, and an important reference for tracking global tech-stock trends.

Nasdaq’s market maker system

Part of Nasdaq’s electronic advantage comes from its distinctive market maker (Market Maker) system. Market makers are independent securities dealers that continuously provide bid and ask quotes for specific stocks to ensure market liquidity.

Each stock listed on Nasdaq must have at least two market makers quoting continuously. For actively traded large-cap stocks, the number of market makers can reach dozens. This mechanism ensures investors can find counterparties at virtually any time without waiting for another buyer or seller to appear, effectively improving market efficiency.

This differs from the “auction-style” operating model of traditional exchanges, which mainly relies on direct matching between actual buyers and sellers in the market.

How can you invest in Nasdaq?

For Hong Kong investors, it is feasible to trade individual Nasdaq-listed stocks directly. However, to participate in overall index performance, the following approaches are more common.

Participate via exchange-traded funds

Exchange-traded funds (Exchange Traded Fund, or ETF) are a common tool for tracking the Nasdaq-100. Take the Invesco QQQ Trust ETF (ticker: QQQ) as an example: it is one of the world’s largest and most actively traded ETFs, allowing investors to hold, through a single product, a portfolio basket of shares in the 100 leading technology companies.

There is also QQQM, which likewise tracks the Nasdaq-100 but differs from QQQ in features such as expense ratio and per-share price. Investors can compare and choose according to their own needs.

Note： ETF prices fluctuate daily with the market, and investors must bear the corresponding market risk. Past performance does not represent future results. Before investing, you should carefully review the prospectus and relevant risk disclosures.

Trade individual constituents

Investors can also trade individual Nasdaq-listed stocks directly, such as representative companies in the technology sector. This approach requires stronger single-stock analysis capabilities, and volatility may be higher than ETFs that track an index. Investors who want to learn more about U.S. stock opportunities can refer to Longbridge Securities’ investment products page to understand the range of markets available for trading on the platform.

Risks you must understand before investing in Nasdaq

Historically, Nasdaq indices have gone through multiple up-and-down cycles and exhibit clear volatility. Before participating, investors must fully understand the following risks.

Concentration risk

The Nasdaq-100’s defining feature—and its main source of risk—is its high concentration in a small number of mega-cap tech stocks. The combined weight of the top 10 constituents has long remained above half of the index’s total weight. This means that if several leading names perform poorly, the entire index can be materially dragged down, and diversification benefits are relatively limited.

Interest-rate sensitivity

Valuations for growth-oriented tech stocks are often built on high expectations for future earnings. When market interest rates rise, the present value of future cash flows declines, putting greater pressure on high-valuation tech names. As a result, the index is particularly sensitive to interest-rate policy.

Industry volatility risk

The technology sector naturally carries higher business risk, including rapid technological change, shifts in regulatory policy, and uncertainty in corporate earnings forecasts. Especially when market sentiment changes quickly, tech stocks often swing more than other traditional sectors.

Before considering Nasdaq-related investments, investors are advised to first deepen their market knowledge through Longbridge Academy and use the Market Data Tools to track index trends, formulating an investment plan aligned with personal risk tolerance.

FAQs

Is Nasdaq an exchange or an index?

Both. Nasdaq itself is a stock exchange where companies list and investors trade shares. “Nasdaq indices,” by contrast, are market indicators calculated based on stocks listed on the exchange to reflect overall market performance. When the media report that “the Nasdaq rose or fell today,” they usually mean changes in the Nasdaq Composite or the Nasdaq-100.

How does Nasdaq differ from the S&P 500?

The S&P 500 includes 500 large companies listed across major U.S. exchanges, with a relatively balanced sector mix spanning technology, financials, healthcare, energy, and more. By contrast, the Nasdaq Composite has more constituents but a higher weighting in technology, and its volatility is typically higher. The two indices emphasize different things and together serve as important reference tools for observing the U.S. equity market.

How can Hong Kong investors trade Nasdaq-related products?

Hong Kong investors can trade U.S. stocks or ETFs listed on Nasdaq through platforms operated by licensed brokers. Longbridge Securities holds the relevant licenses issued by the Hong Kong Securities and Futures Commission and provides U.S. stock trading services. For information on opening a U.S. securities account, the W-8BEN tax form, and basic trading rules, please refer to the Beginner’s Guide to U.S. Stock Investing: Essential Account Opening and Trading Strategies for Hong Kong Investors.

What are Nasdaq’s trading hours?

Nasdaq’s regular trading hours are 9:30 a.m. to 4:00 p.m. U.S. Eastern Time (i.e., 9:30 p.m. to 4:00 a.m. Hong Kong time during daylight saving time, and 10:30 p.m. to 5:00 a.m. during standard time). Some brokers also offer pre-market and after-hours extended sessions, but liquidity and volume are usually lower than during regular hours. In addition, U.S. markets observe public holidays and early-close arrangements. You can refer to the U.S. Stock Market Holiday Schedule, Closures, Early Trading, and Essential Strategies for Hong Kong Investors to plan your trades in advance.

Conclusion

Nasdaq is not only a stock exchange, but also a barometer of global technological innovation. Understanding its structure, index classifications, and operating mechanisms is an important foundation for getting to know the U.S. equity market. Whether you are considering direct investment in individual tech stocks or participating via ETFs to capture index performance, you should fully understand the associated risks and prudently formulate a strategy based on your investment objectives and risk tolerance.

Which investment tool to choose depends on your investment goals, risk tolerance, market views, and level of experience. No matter which tool you choose, you must fully understand how it works, its risk characteristics, and trading rules, and establish a sound risk management plan. You can learn more investment knowledge through Longbridge Academy or by downloading the Longbridge App.