Open source programming tool on the rise: Content management systems
Even today, most programmers fill up text files and push a button to compile and run the code. This is changing as users gain more and more control to alter the software as it runs.
Drupal websites, for instance, blend traditional modules with additional inserted code. Although much of this occurs on the back end, Drupal can be configured to allow users to include PHP code in data fields, enabling programmers to update a bit of running code on the fly. They're usually smart enough to do this on a test version, but sometimes they update hot, running code because it's not that hard. What could possibly go wrong?