WORA

From APIDesign

Write Once Run Anywhere (WORA) is the original promise of Java. The goal is to write the code once and execute it in multiple environments. This has become an increasing reality since Java's introduction in mid-90ies - with one exception - the browser.

These days JavaScript (the default language of the browser) becomes increasingly popular in other environments (including server side) and may be seen to provide more WORA than Java - which is the reason I decided to start the Bck2Brwsr project (and why others develop VMs for iOS).