The document discusses installing the Groovy engine in Apache Jmeter to enable scripting capabilities. It is a 4 step process: 1) Download the latest Groovy version, 2) Extract and copy Groovy jar files to the Jmeter lib/ext folder, 3) Restart Jmeter, 4) Add a JSR223 sampler where Groovy will be available as a scripting option to write and execute Groovy scripts.