In this chapter, we looked at the general architecture of Apache Lucene: how it works, how the analysis process is done, and how to use Apache Lucene query language. In addition to that, we discussed the basic concepts of Elasticsearch, its architecture, and internal communication.

In the next chapter, you'll learn about the default scoring formula Apache Lucene uses, what the query rewrite process is, and how it works. In addition to that, we'll discuss some of the Elasticsearch functionality, such as query templates, filters, and how they affect performance, what we can do with that, and how we can choose the right query to get the job done.