Search intent is the goal somebody pursues with a query. The same words can carry very different intentions, and search engines assess content by whether it serves the prevailing one. A page that is excellent in substance and serves the wrong intent does not rank.
The four basic types
A four-way split is conventional. Informational queries seek knowledge — how something works, what a term means. Navigational queries head for a particular destination, usually a known brand or site. Commercial queries prepare a decision — comparisons, alternatives, costs, experiences. Transactional queries want to act — buy, book, enquire, download.
The results page reveals the intent
The most reliable way to determine intent behind a query is not reasoning but looking. What a search engine returns for a query is its interpretation of the prevailing intent. If it mostly shows guides, the query is informational; if it shows product pages, it is transactional. Writing against that picture is not competing for a better place but for a place in a different category.
Mixed intent
Some queries carry several intents at once, recognisable from mixed results pages — guides beside product pages beside comparisons. In those cases, deciding which intent to serve is strategic. Trying to serve all of them at once usually produces a page that fulfils none of them convincingly.
What an intent mismatch costs
A mismatch is expensive because it acts twice. The page ranks worse, because it does not match the expected answer. And the visitors who arrive anyway bounce, because they were looking for something else. The most common case is a sales page optimised for an informational query — both goals are missed.
What follows for page structure
Structure follows intent. Informational pages open with the answer and deepen afterwards. Commercial pages need an honest comparison, including the cases where the alternative fits better. Transactional pages need short paths to action and no long explanations. The same information belongs arranged differently depending on intent.
Practical consequence
Before creating any new content, a look at the actual results page for the target query pays off. Those two minutes decide the structure of the page and, in case of doubt, save the work of writing content that answers the wrong question.