Primary sources are original materials or documents that provide firsthand accounts or direct evidence of an event, topic, or time period. These sources can include letters, diaries, speeches, photographs, newspapers, government documents, interviews, and artifacts. Primary sources are the foundation of historical research, as they offer the most direct and unfiltered perspective on a particular subject. Researchers often use primary sources to analyze and interpret past events, gain insights into the thoughts and experiences of individuals, and construct narratives based on verifiable evidence.