Prometheus is an open-source monitoring system and time series database that offers a comprehensive solution for collecting and analyzing metrics and telemetry data. With a highly dimensional data model, Prometheus allows users to identify time series data by metric names and key-value pairs. The system offers powerful queries using PromQL, enabling users to slice and dice collected data to generate ad-hoc graphs, tables, and alerts. Prometheus also provides multiple modes for visualizing data, including a built-in expression browser, Grafana integration, and a console template language. In terms of storage, Prometheus stores time series data in memory and on local disk using a highly efficient custom format. It achieves scalability through functional sharding and federation techniques. The system is designed for simple operation, with each server operating independently and relying on local storage. Additionally, Prometheus is written in Go and all of its binaries are statically linked, making deployments easy. One of the key features of Prometheus is its precise alerting capability. Alerts can be defined using the flexible PromQL language and maintain dimensional information. An alertmanager handles notifications and silencing. Prometheus offers a range of client libraries that facilitate easy instrumentation of services. It supports over ten programming languages, and custom libraries can be implemented easily. The system also provides various integrations, allowing users to bridge third-party data into Prometheus. Examples of existing exporters include system statistics, Docker, HAProxy, StatsD, and JMX metrics. As an open-source project, Prometheus is community-driven and available under the Apache 2 License on GitHub. It has gained recognition in the industry, with the Cloud Native Computing Foundation graduating it as a project. The system is used by a diverse range of users, contributing to its growing popularity and reliability. Overall, Prometheus offers a robust and feature-rich solution for monitoring, managing, and analyzing metrics and telemetry data. Its strengths lie in its dimensional data model, flexible PromQL queries, efficient storage, simple operation, precise alerting, extensive client libraries, and integrations. As an open-source tool, Prometheus provides users with the benefits of active community support and continuous development.