Overview of Google Apps Script
Google Apps Script is a scripting language based on JavaScript that lets you do new and cool things with Google Apps like Docs, Sheets, and Forms. There's nothing to install — we give you a code editor right in your browser, and your scripts run on Google's servers.
If you're new to JavaScript, Codecademy offers a great course for beginners. (Note that this course was not developed by and is not associated with Google.)