Indeed, while internet technologies were a large part of the economic boom of the time period, it was not the only factor evident. The growth of free trade with initiatives like the North American Free Trade Agreement (NAFTA) as well as a growing global market helped to increase economic prosperity to more parts of the world and to America. The growth of markets in Eastern Europe and Russia, with the fall of Communism, helped to provide a greater market to many American businesses. At the same time, more economies began a liberalisation of their economic practices. An example of this would be a decrease in nations of taxation on businesses and free market enterprising. Nations such as India took active steps to move away from a government controlled economic sector and privatize businesses, helping to increase economic competitiveness and spinning off into American business prosperity.
I think there's quite a bit of truth to this statement. Both the internet boom and the spinoff industries and services it created contributed to unprecedented and sustained economic growth in that time period.
In 1992, the year immediately after the Persian Gulf War and the Cold War ended, there was a recession (this was largely the reason George H. W. Bush was not re-elected).
As the impact of internet technology started to take effect, it created new businesses in a place there had never been businesses before: cyberspace. You could run a store without a storefront, go shopping in your robe and slippers while never leaving your house, and communicate in a very cheap and efficient manner through email. All of these served to stimulate and encourage economic growth.
My guess is that your textbook has some facts that you are expected to find and use. I suggest you look for them.
People say that the internet and its growth were very important in the economic boom that happened in the 1990s. This is especially true of the boom of the late 1990s.
However, there were also a number of other things going on. The Cold War ended in the early 1990s. This made people feel very confident and helped the economy. The price of oil was very low. Finally, some people argue that a tax cut in 1997 helped cause much of the growth as well.
It is impossible to know which things mattered how much, but most people think all of these things had some impact.