Google Tag Manager is a free tool that helps website owners manage and deploy marketing tags without needing to modify the code directly. Tags are small snippets of code that track user behavior, gather analytics, and enhance marketing efforts. With Google Tag Manager, you can easily add or update tags for services like Google Analytics or Facebook Pixel from a user-friendly interface. Using Google Tag Manager simplifies the process of tracking website performance and user interactions. Instead of relying on developers for every change, marketers can quickly implement and test new tags, making it easier to optimize campaigns and improve overall website functionality.