— The app you develop and the IDE is a single persistent image. On deployment, you can strip away the IDE part.<p>— This means: no source files (code is stored as OO dataset), no need to save &#x2F; recompile &#x2F; etc.<p>— No keywords. All control flow is modeled as methods. Like: (a &gt; b) ifTrue: doSomething else: doSomethingElse.<p>— Everything is dynamic and hackable. Want to redefine the meaning of true and false? Want to change inheritance hierarchy at runtime? Want to write self-modifying code? Be my guest. For everything, source code is accessible and modifiable. At runtime (there is no compile time).<p>And much more.