Facebook Pixel

The Facebook Pixel is a piece of code that businesses place on their websites to track website activity and measure the effectiveness of Facebook ads. When someone visits your website and interacts with it, the Pixel sends information about that activity back to Facebook. This information can be used to target your ads more effectively, create custom audiences, and measure the impact of your campaigns. The Pixel allows you to track conversions, optimize ad campaigns, and better understand your customer journey.

Website: https://www.facebook.com/business/products/pixel