Glulx is a 32-bit portable virtual machine intended for writing and playing interactive fiction. It was designed by Andrew Plotkin to relieve some of the restrictions in the venerable Z-machine format. For example, the Z-machine provides native support for 16-bit integers, while Glulx natively supports 32-bit integers.The Inform compiler, starting with version 6.30, can produce either Z-machine or Glulx story files.