Cloud IDEs provide cloud-based development environments that allow developers to access, collaborate on, and maintain their code from anywhere. Some key benefits include being able to access code from any computer, enabling live collaboration between developers anywhere, and having the maintenance of the environment handled by someone else. Popular cloud IDEs include Cloud9, Codenvy, and Codeanywhere, which offer features like syntax highlighting, autocompletion, debugging, and connections to version control systems. They differ in pricing models, supported languages, and additional capabilities.