Apart from searching, the second most important functional strength of Elasticsearch is analytics. Yes, what was originally known as just a full-text search engine is now used as an analytics engine in a variety of use cases. Many organizations are running analytics solutions powered by Elasticsearch in production.

Conducting a search is like zooming in and finding a needle in a haystack, that is, locating precisely what is needed within huge amounts of data. Analytics is exactly the opposite of a search; it is about zooming out and taking a look at the bigger picture. For example, you may want to know how many visitors on your website are from the United States as opposed to every other country, or you may want to know how many of your website's visitors use macOS, Windows, or Linux.

Elasticsearch supports a wide variety of aggregations for analytics. Elasticsearch aggregations are quite powerful and can be applied to various data types. We will take a look at the analytics capabilities of Elasticsearch in Chapter 4, Analytics with Elasticsearch.