API Integration refers to the process of connecting different software applications through their Application Programming Interfaces (APIs). This allows them to communicate and share data seamlessly, enabling users to access features and information from multiple systems without manual input. By using API Integration, businesses can streamline their operations, improve efficiency, and enhance user experiences. For example, a payment gateway API can be integrated into an e-commerce platform, allowing customers to make purchases directly without leaving the site. This integration simplifies processes and fosters better collaboration between different software tools.