---
title: "How to Learn Elasticsearch"
description: "Learn about Elasticsearch features, use cases, and core data structures."
image: "https://assets.bytebytego.com/diagrams/0182-elastic-search.jpeg"
createdAt: "2024-03-08"
draft: false
categories:
  - caching-performance
tags:
  - Elasticsearch
  - Search
---

![](https://assets.bytebytego.com/diagrams/0182-elastic-search.jpeg)

Based on the Lucene library, Elasticsearch provides search capabilities. It provides a distributed, multitenant-capable full-text search engine with an HTTP web interface and schema-free JSON documents. The diagram above shows the outline.

## Features of ElasticSearch:

* Real-time full-text search
* Analytics engine
* Distributed Lucene

## ElasticSearch use cases:

* Product search on an eCommerce website
* Log analysis
* Auto completer, spell checker
* Business intelligence analysis
* Full-text search on Wikipedia
* Full-text search on StackOverflow

The core of ElasticSearch lies in the data structure and indexing. It is important to understand how ES builds the **term dictionary** using **LSM Tree** (Log-Strucutured Merge Tree).