The QQQ ETF tracks 100 of the largest domestic and non financial international companies. Ranking is based on market capitalization in the Nasdaq stock market. By definition it is a broad index fund that excludes financial based companies.
While the QQQ is heavily weighted in technology stocks, it is not considered to be a tech fund. It has always been associated with technology stocks and the technology sector. Many technology companies will list their stocks on the Nasdaq market, particularly the largest more successful companies in the world. Since QQQ is focused on the Nasdaq, it is not surprising that it is overweight to some degree in technology related equities.
Diversity has always been important to many investors. While QQQ avoids financials, it has diversified into Biotechs and some consumer stocks such as Starbucks Corp. (SBUX). With a good mix of consumer, biotech and technology investments, QQQ may be destined to outperform over the long term. This investment strategy has served it well since 2013. QQQ has outperformed the Dow Jones Industrial average over the past three years.
The future appears to be bright for QQQ. The world is increasingly dependent on technology and this trend appears to be accelerating. Biotech is also expected to do well as aging baby boomer appetites for life extending and quality of life demands increase. Drug makers and biotechs are well positioned to meet these demands. Technology companies are also developing solutions to meet the needs of aging baby boomers in addition to the worlds increased demand for technology solutions.
from Stock and Options Trading http://www.stocks-options-trading.com/history-qqq/