Beats are open source data shippers. They are single-purpose tools. Some Beats are created and maintained by the company Elastic. Those are listed in this Beats overview. The community creates an additional wide range of Beats. Most of the Beats should work out of the box with the Graylog Beats input, but some might need to adjust settings.
For most Beats, the logstash output is sends messages to Graylog. It makes no difference what Beats receive the signals as long as they follow the protocol. Note that the TCP input is the only option.
This input can make use of TLS and certificates for authentication.
See also: