The additional useful knowledge a resource contributes beyond information already available to its audience.
In editorial planning, information gain means the useful knowledge a resource adds for its audience. That addition might be a new finding, a clearer explanation, a worked example or a practical distinction missing from common answers. The starting question is what the reader understands better afterward.
Additional length alone does not establish additional value. Repeating the same advice in different words can make the answer harder to use. A short explanation that resolves an important ambiguity may contribute more than a long list assembled from familiar sources.
This glossary uses the term as an editorial concept, not as a claim that a public Google information-gain score is available for a page. Originality should remain connected to accuracy and reader needs. An unusual assertion with no evidence is not a useful improvement over a reliable existing answer.
Takeaway: Identify the specific understanding your page contributes before expanding it. Use relevant experience, clear examples or documented evidence rather than manufacturing novelty.
Example
A furniture repair business explains how it distinguishes cosmetic surface damage from a problem requiring further assessment, using genuine permitted photographs and clearly stated limits. That can answer a customer question more effectively than repeating that professional repairs are high quality.
What to check
Ask a reviewer what new or clearer understanding the page provides. Remove repeated material that does not help. Verify any original claims, and do not invent local prices, project results or timelines merely to make the resource seem distinctive.
For more detail, see Creating helpful, reliable, people-first content.