This document discusses monitoring Elasticsearch and Nginx with Prometheus and Grafana. It introduces the speaker and their work at LINE developing a browser log collection system using Nginx and Elasticsearch. It then covers setting up Prometheus to monitor Nginx using the nginx_exporter plugin, which scrapes Nginx status pages. Metrics on request rates, connections and response times are shown. Elasticsearch is monitored using the elasticsearch_exporter. Example Grafana dashboards visualizing metrics from these exporters like request rates, Java heap usage and connection counts are also presented. The speaker expresses that Prometheus and Grafana work well together for time-series monitoring and the exporters provide a convenient way to export metrics.