Angular.js is a web application framework that helps developers build dynamic web pages. Imagine you're building a house, and Angular.js is like a pre-built structure that provides the foundation and basic utilities. This framework lets developers focus on adding the unique features and functionality of their web application without needing to build everything from scratch. Angular.js is known for its two-way data binding, which automatically updates the displayed information (view) whenever the underlying data (model) changes, and vice versa. This makes it easier to manage complex web applications and ensures that the information displayed is always up-to-date.