Print and online sources differ mainly in their medium, permanence, editorial process, and how they're accessed and updated—though the line between them has blurred considerably.
Format and access Print sources are physical materials—books, newspapers, magazines, journals—that exist on paper and must be physically obtained (bought, borrowed, or found in an archive). Online sources are digital and accessed via the internet, including websites, e-books, digital databases, and web-based news articles.
Permanence and revision Print is fixed once published; a printed page cannot be edited after distribution, so any errors or updates require a new edition or printing. Online content can be edited, updated, or removed at any time, which makes it more current but also less stable—a source cited today might change or disappear tomorrow (a problem researchers call "link rot").
Editorial oversight Traditionally, print sources (especially books and established newspapers/journals) undergo formal editorial review, fact-checking, and sometimes peer review before publication, lending them a reputation for reliability. Online sources vary enormously in quality: some (like digital versions of peer-reviewed journals or established news outlets) maintain the same rigorous standards, while others (blogs, social media, self-published sites) have little to no oversight, making credibility evaluation more important.
Speed and reach Online sources can be published and distributed almost instantly to a global audience, making them ideal for breaking news or rapidly evolving topics. Print production is slower, involving typesetting, printing, and distribution, so it's better suited to in-depth, long-form, or evergreen content.
Citation and verification Because online material can change, citation styles often ask for access dates or archived URLs, while print citations rely on stable details like publisher, edition, and page numbers.
Overlap Many sources now exist in both forms—a newspaper article might appear in print and on the publisher's website—so the content can be identical even though the medium differs. When evaluating any source, checking the author, publisher, evidence, and purpose matters more than whether it's print or digital.