Internet Research is the practice of using the Internet, especially the World Wide Web, for research. To the extent that the Internet is widely and readily accessible to hundreds of millions of people in many parts of the world, it can provide practically instant information on most topics, and is having a profound impact on the way in which ideas are formed and knowledge is created.
Research is a broad term. Here, it is used to mean "looking something up (on the Web)". It includes any activity where a topic is identified, and an effort is made to actively gather information for the purpose of furthering understanding. Common applications of Internet research include personal research on a particular subject (something mentioned on the news, a health problem, etc), students doing research for academic projects and papers, and journalists and other writers researching stories.
It should be distinguished from scientific research - research following a defined and rigorous process - carried out on the Internet; from straightforward finding of specific info, like locating a name or phone number; and from research about the Internet.