The speaker begins by introducing themselves as an engineering manager at Grafana Labs and an active member of the Prometheus team. They explain that the talk will consist mostly of live demos and will showcase an example application instrumented with open telemetry and monitored using Grafana and open source databases. They start by demonstrating how metrics can be visualized using Grafana, specifically focusing on a metric named HTTP server duration, which represents the duration of HTTP requests. They show how Prometheus queries can be used to calculate request rates, error rates, and duration percentiles, and how these metrics can be used to create a metrics dashboard. The speaker then moves on to tracing and shows how traces can be visualized and searched using Loki, an open-source logs database. They explain the concept of spans and show how spans can be used to understand the latency behavior of an application. They also demonstrate how traces can be used to identify errors and performance bottlenecks. Finally, the speaker showcases logs and demonstrates how logs can be searched and queried using Loki. They explain how trace IDs can be included in log data, allowing for easy navigation between logs and traces. The speaker concludes by mentioning that metrics, traces, and logs are related and can be used together to gain insights into the behavior and performance of an application. They encourage the audience to explore the demo further and provide a link to the GitHub repository where the demo can be found. The talk ends with a brief Q&A session, where the speaker answers questions about the impact of monitoring being down on an application and the ability to link metrics with trace data.