Not too long ago I became obsessed with Prometheus.
I'd heard about it for a while, knew it was powerful, and couldn't quite understand how everything fit together.
The documentation is extremely verbose for good reason but it took playing with it for a while for everything to click.
This post is a rather concise and extensive overview that goes a long way in expressing the basic concepts to my developer brain.
In their simplest form, exporters expose an HTTP endpoint of /metrics with the output being statistics in Prometheus' format.
The real power of Prometheus comes when you expose your own /metrics endpoint and have Prometheus consume the statistics you generate.
This post is also a very good introduction with the se ...