Invesco QQQ Trust, Series 1 (QQQ)

QQQ tracks the Nasdaq-100 — the hundred largest non-financial companies listed on Nasdaq. It is close to a technology index without being one.

Selection is by listing venue rather than by industry: the index holds companies traded on Nasdaq, excluding financials. In practice that produces a very high technology weight alongside meaningful consumer and biotechnology exposure. Understanding the rule matters: the fund does not promise sector coverage, it reproduces a venue's rule.

Capitalisation weighting with caps means high concentration: a handful of top positions drive much of the movement. That makes the fund markedly more volatile than the broad market — stronger in technology rallies and deeper in drawdowns.

QQQ is highly liquid with a deep options market, so it serves both as a long-term technology bet and as a short-term instrument. A cheaper version of the same fund exists for long holding periods — with identical holdings, the difference is fee and liquidity alone.