Up to now, most of the times we talked to ElasticSearch with the REST API using an HTTP request, we were using JSON-structured data to do that, regardless of whether it was a mappings change, alias creation, or document indexation. A similar situation arises when we want to send more than a simple query to ElasticSearch—we structure it using JSON objects and send it to ElasticSearch. This is called Query DSL. In a broader view, ElasticSearch supports two kinds of queries, basic ones and compound ones. Basic queries such as the term query are used just for querying. We will cover these in the Basic queries section in this chapter. The second type of query is the compound query, such as the bool query, which can combine multiple queries. We will cover these in the Compound queries section in this chapter.
However, this is not the entirety of the picture. In addition to these two types of queries, your query can have filter queries , which are used to narrow your results...