The blog post, part of a three-part series on monitoring Apache performance, explores how the Apache HTTP Server functions and identifies key performance metrics critical for efficient operation. Apache, an open-source web server, is praised for its customizability and modular architecture, which facilitates diverse use cases and contributions without disrupting core functionalities. However, its one-process-per-connection model can struggle with high concurrency, prompting interest in other web servers like NGINX and IIS. Important metrics for monitoring include request processing time, rate of requests, resource utilization, and error rates, all retrievable via Apache's mod_status and access logs. The post also discusses the Multi-Processing Modules (MPMs) in Apache—prefork, worker, and event—which dictate resource management and influence performance metrics, particularly under different operating systems. The series aims to guide users in collecting and analyzing these metrics to preempt and address performance bottlenecks, with subsequent parts detailing data collection and monitoring techniques.