The "executablePath" parameter in Puppeteer is used to specify the path to the browser executable that Puppeteer should use. This allows the user to use a specific version of the browser (e.g. a specific version of Chrome) or to use a browser that is not the default one on the system.
For example, if you have Chrome Canary installed on your system and you want to use it with Puppeteer, you would specify the path to the Canary executable as the value for the "executablePath" parameter.