The Sun Labs Lively Kernel is an interactive web application development environment developed at Sun Microsystems Laboratories. The Lively Kernel supports desktop-style applications with rich graphics and direct manipulation capabilities, but without the installation or upgrade hassles that conventional desktop applications have. The system is written entirely in the JavaScript programming language, a language supported by all the web browsers, with the intent that the system can run in commercial web browsers without installation or any plug-in components. The system leverages the dynamic characteristics of the JavaScript language to make it possible to create, modify and deploy applications on the fly, using tools built into the system itself. In addition to its application execution capabilities, the Lively Kernel can also function as an integrated development environment (IDE), making the whole system self-sufficient and able to improve and extend itself dynamically.