In Angular, the term "services" refers to singleton references to objects and functions that carry out specific tasks. Angular provides several built-in services for everything from manipulating the URL in the browser, running code at regular intervals, and interfacing with Web services to managing asynchronous workflows using javascript promises. This lesson walks through the core services shipped with Angular by providing detailed hands-on examples and covering advanced topics such as promises, strict contextual escaping, and how to interface with various providers to configure the behavior of built-in services.