Highlighting

You have probably heard of highlighting, or even if you are not familiar with the name, you've probably seen highlighted results on the usual web pages you visit. Highlighting is the process of showing which word or words from the query were matched in the resulting documents. For example, if we want to do a search on Google for the word lucene, we will see it in bold in the list of results as shown in the following screenshot:

In this chapter, we will see how to use the Elasticsearch highlighting capabilities to enhance our application with highlighted results.

Getting started with highlighting

There is no better way of showing how highlighting works besides creating a query and looking at the results returned by Elasticsearch. So let's assume that we want to highlight the words that were matched in the title field of our documents to enhance our users' search experience. We search for the crime word again, and to get the results of the highlighting, we send the following query...