The ELK Stack is a collection of three open-source products — Elasticsearch, Logstash, and Kibana. ELK stack provides centralized logging in order to identify problems with servers or applications. It allows you to search all the logs in a single place. It also helps to find issues in multiple servers by connecting logs during a specific time frame.
E stands for ElasticSearch: used for storing logs
L stands for LogStash : used for both shipping as well as processing and storing logs
K stands for Kibana: is a visualization tool (a web interface) which is hosted through Nginx or Apache
ElasticSearch, LogStash and Kibana are all developed, managed ,and maintained by the company named Elastic.
ELK Stack is designed to allow users to take data from any source, in any format, and to search, analyze, and visualize that data in real time.