Primary sources are original records created at the time of an event. That is the part that matters most, because it tells a researcher what kind of evidence is in front of them. A primary source is not a later summary. It is a record made close to the event itself.
I start with that plain fact because the label can be confusing. A diary, a letter, a photograph, a government record, or a newspaper account from the time can all count as primary sources. What they share is direct connection to the event, person, or period under study. They do not come to the reader through a long chain of retelling.
This is why primary sources matter in databases and digital collections. A source can be digitized and still be primary. The format does not change the basic question. What was it, who made it, and when was it made? Those are the first checks I want to make.
That sounds simple, but the line is not always neat. A source can be primary for one question and secondary for another. A newspaper editorial from 1910 is primary for studying views in 1910. It is not primary evidence for the event that happened after it was written about. Context sets the role.
I think that is the key habit a researcher needs. Do not ask only whether a source is old. Ask whether it was created at the time, and whether it gives direct evidence for the question at hand. A scanned image, a transcript, or a digital copy may be enough for access. Still, the researcher should know what the item is and how it came into the database.
That is where library work becomes practical. A digital collection is only as useful as its notes on coverage, source type, and limits. If the publisher does not say whether an item is an original record, a later copy, or an edited version, the user has a problem. The record may still be useful, but the terms of use are unclear.
I find that uncertainty worth saying out loud. Not every item that looks like a primary source is one in the same way. An edited diary, a translated letter, or a newspaper reprint can blur the line. Provenance, the history of where a source came from, matters here. So does the version the database shows.
The honest limit is this: “primary source” is not a fixed box. It depends on the research question, the field, and the record’s own history. In a history class, the term often means firsthand evidence from the time studied. In another field, the same item may serve a different purpose. The label helps, but it does not think for us.
So I keep coming back to the same plain answer. Primary sources are original records created at the time of an event. Once that is clear, the next task is not to praise the source, but to identify its form, its date, and its limits before trusting it too far.
That is also the promise behind The Source List: one digital source worth knowing, one search tip, and one honest limitation. That is the right scale for this kind of work, because clear evidence begins with clear terms.