The Beats are open source data shippers that you install as agents on your servers to send different types of operational data to Elasticsearch. Beats can send data directly to Elasticsearch or send it to Elasticsearch via Logstash, which you can use to parse and transform the data.
Packetbeat, Filebeat, Metricbeat, and Winlogbeat are a few examples of Beats. Packetbeat is a network packet analyzer that ships information about the transactions exchanged between your application servers. Filebeat ships log files from your servers. Metricbeat is a server monitoring agent that periodically collects metrics from the operating systems and services running on your servers. And Winlogbeat ships Windows event logs.
If you have a specific use case to solve, we encourage you to create your own Beat. We created an infrastructure to simplify the process. The libbeat library, written entirely in Golang, offers the API that all Beats use to ship data to Elasticsearch, configure the input options, implement logging, and more.