All sites come with a basic search engine that allows your visitors to quickly find content based on keywords.
What Content Is Indexed?
At a high level, a search index is a mapping of keywords to content items. When your site indexes a content item, it scans its content to create this index, so that when a visitor searches for a keyword, the site knows which content to show in the search results. All text that's included on the full detail page of the content item is typically included in the index, including the title.
By default, all published content items on your site are included in the search index. This includes pages, but will also include news articles, events, and person pages if you have those optional modules enabled. If WDS has developed any custom content types for your site, those are likely included in the search index as well.
At this time, there's no method to prevent individual content items from being included in the index, with the exception of simply unpublishing the content. In the future this capability may be added.
Changes to content (e.g. new content, edits to existing content) may take up to 15 minutes before being indexed in your search.
Search Results Page
Visitors that use your site's search in the header will be brought to a search results page that shows the title and a snippet of text (if available) for each content item that matched the keywords.
The snippet of text will typically include words before and after the matched keyword to help provide some context to the visitor as to why that page was returned in the search results. If the keyword appears multiple times on the page, it may be included multiple times in the snippet.
The system that generates the snippet of text is not perfect, and you may not always observe ideal results. Also note that sometimes a snippet of text will not be generated. For example, if you published a page but did not fill in any body text, there won't be a snippet returned in the search results.
Visitors that click a page from the search results page will see some of the keywords they searched for highlighted on the page. This is to help the visitor find the area of the page that's relevant to their search. *Some sites with custom themes will not see this behavior.
Search results are ranked based on the relevance of the content to the keywords that were searched. The relevance is determined both by the frequency a keyword appears on a page and what part of the content that keyword belongs to.
More weight is provided to keywords that appear in a content item's title than its body. However, if the keyword appears many times in the body, it may still outrank a page that only has the keyword in its title.
If you want to artificially boost some content items higher in search results for a specific keyword, the Page, News, Event, and Person content type have a Search Keywords field. Keywords entered here are weighted very heavily, even more than the page title, so that if a visitor searches for that keyword, it dramatically increases the chance that content item will appear at the top of the results.
Content Type Facet
Site admins can optionally enable a facet (sometimes referred to as a refinement or filter) for content type on the search results page. This allows your visitors to refine search results by content type, similar to how you might browse an online shopping website. To enable this feature, visit Configuration > Search and Metadata > Search Settings.