There are two basic kinds of sources you can use in your papers, primary and secondary. Knowing the difference is kinda crucial for performing serious academic research. A primary source is the ground-level evidence for any discipline. Evidence, by its nature, can't be right or wrong. It just is. What we do with it is where things get interesting. And that brings us to secondary sources. These are anything created using primary sources. Often they take the form of books and articles. What constitutes a primary or secondary source isn't absolute. It varies with the discipline you're studying. In history, a primary source can be a first-hand account of a historical event. A secondary source can be an article written using information from that first-hand account. In literature, a primary source can be a novel or poem. A secondary source can be an article written about that novel or poem. In science, a primary source can be an article describing an empirical study. A secondary source would be an article written about someone else's study. Seems straightforward, but watch out. whether a source is primary or secondary depends on the information it contains and how you’re gonna use it. Like this fish, which can be a pet or dinner. Let's focus on primary sources, which are the ground-level evidence for any discipline. So what exactly makes something a primary source? Take an example from history. The Ukrainian Terror-Famine: Soviet persecution of Ukrainian farmers who opposed collectivization, resulting in as many five million deaths. It wouldn't be safe, or, you know, possible, to travel in time back to the 1930s to study it in person, so we rely on the best evidence available, like these letters, which contain some of the only known first-hand accounts. They're considered primary sources because they're the closest we can get to actually observing the Terror-Famine. Now for secondary sources, which are anything created using primary sources. Secondary sources are typically articles or books written by scholars who've examined primary sources. Say a scholar is interested in the origin of the Terror-Famine. What's its deal? Where'd it come from? That scholar would read primary source documents, like these letters, to learn about why this terrible thing happened. Anything this scholar produces using that information, like a book or an article, would be a secondary source. Great, but I said that whether a source is primary or secondary depends on the information it contains, and how you're gonna use it. Check it out. This is a diagram of primary and secondary sources in relation to the Terror-Famine. The historical event produces first-hand accounts, examined by a scholar, who produces books and articles. Now, let's say the scholar is also a famous politician, and you want to study him instead. When the focus shifts to the scholar, the secondary sources produced by that scholar become primary sources, because they can be used as evidence for the thing we're studying, which is the person who wrote them. So, are primary sources just plain better than secondary sources? Not necessarily. Consider this. Imagine a scholar is really clever, and puts a huge amount of effort into analyzing primary sources and combines everything into a cohesive, insightful analysis of the Terror-Famine, tracing its origin and repercussions. Even if we have access to the same primary sources, and could read the languages they're written in, that article could save us the time it would take to figure out the entire historical event on our own, and might even supply insights that we might not have come up with. The point is, primary and secondary sources aren’t in competition. It’s more like a friendly conversation that produces new knowledge.