Apache Bench (ab)

Apache Bench (ab) is a simple, command-line tool for benchmarking HTTP servers. It is incredibly lightweight and easy to use, making it a go-to tool for quick, one-off performance checks. While it lacks the advanced features and reporting of modern tools, it is perfect for testing the raw throughput of a web server. It is a staple in every developer's toolkit for quick sanity checks during development.

However, it is not suitable for complex, multi-step scenarios or distributed load testing, as it is limited to a single machine.