Gatling is an open-source load and performance testing tool for web applications, built to help companies anticipate and prevent issues like slowdowns and crashes. It is a script-based platform where tests are written as code in languages like Scala, Java, or Kotlin, which can be easily integrated into development workflows and CI/CD pipelines. Gatling is known for its high performance, allowing millions of virtual users to be simulated with minimal resources, and it offers both a free Community Edition and a commercial Enterprise version with added features like a web interface.