A "source" refers to the origin or starting point of information, materials, or data. In research, sources can include books, articles, websites, or interviews that provide evidence or insights on a particular topic. Reliable sources are essential for ensuring the accuracy and credibility of the information presented. In the context of journalism, a source can also refer to a person who provides information to a reporter. This can include eyewitnesses, experts, or officials. Journalists often verify their sources to maintain integrity and trustworthiness in their reporting, ensuring that the information shared is factual and well-supported.