The Nasdaq Composite (^IXIC 0.52%) is one of the U.S. stock market's three major indexes, along with the S&P 500 and Dow Jones. It contains virtually every stock listed on the Nasdaq stock exchange and has been the best-performing index of the three over the past decade by a significant margin.

August was a strong month for the index, with a 1.58% increase. Leading the way were Intel (INTC 0.47%), Applovin (APP -0.91%), and IDEXX Laboratories (IDXX -0.33%). All three companies finished the month up at least 21%.

^IXIC Chart

Data by YCharts.

Intel's good month was influenced heavily by the U.S. government announcing an investment in the company that would give it a roughly 10% equity stake. It also got a bump from a $2 billion investment from SoftBank. These investments aim to give Intel a boost to help the U.S. have a strong domestic semiconductor manufacturing company that can compete with companies like Taiwan Semiconductor Manufacturing.

Applovin benefited from a strong second-quarter earnings report that shed light on the growth of its ad-tech business. Its overall revenue increased 77% year over year to $1.26 billion, and net income increased 164% to $820 million. Maybe more impressive is the fact that its earnings per share (EPS) almost tripled to $2.39.

IDEXX Laboratories also had a good second quarter, beating estimates and raising its full-year revenue and earnings guidance. Its revenue increased 11% year over year to $1.1 billion, and it raised its full-year guidance by around $90 million to $4.2 billion-$4.28 billion.