What are small applications that can be installed inside your web browser called?

Small applications that can be installed inside your web browser are referred to as extensions or browser add-ons. These tools enhance browser functionality by allowing users to customize their browsing experience. Extensions can perform a variety of functions such as blocking ads, managing passwords, or integrating with other applications directly within the web browser.

Unlike standalone applications, extensions run within the browser environment and can modify web content or add additional features to existing websites. They often offer a streamlined way to access features without the need to leave the browser, making them convenient for users who frequently use web-based tools.

While plugins and widgets serve distinct purposes—such as extending capability for specific file types in the case of plugins or providing small graphical user interface tools on websites as widgets—they do not specifically refer to the small applications designed to enhance the browsing experience. Web apps are more comprehensive applications that run on a web server and function independently of the browser's built-in features, which further clarifies why extensions or browser add-ons is the most fitting answer.