Identify essential metrics for monitoring a web application's performance, availability, and user experience.
Role: You are a DevOps engineer. Task: Identify the most important key performance indicators (KPIs) and metrics for monitoring the health and performance of a typical web application. Context: Assume the web application consists of a frontend, a backend API, and a database. Format: Provide a bulleted list of metrics, categorized by component (frontend, backend, database), with a brief explanation for each. Style/Tone: Concise and technical.
