Environment > Distributing IDL Applications > Virtual Machine Applications

# Virtual Machine Applications

An IDL Virtual Machine is a runtime version of IDL that can execute IDL `.sav` files without an IDL license. It is designed to provide IDL users with a simple, no-cost method for distributing IDL applications. It runs on all IDL-supported platforms, and does not require a license to run. This utility allows you to easily distribute IDL SAVE files to your colleagues or your customers, without requiring them to own an IDL runtime license.

Beginning with IDL 6.0, the IDL Virtual Machine is included with all IDL distributions. For the benefit of developers who need to debug applications designed to run in this environment, the IDL Virtual Machine can be started explicitly. Otherwise, if a SAVE file program is run without an IDL license, IDL defaults to the IDL Virtual Machine mode.

If you have received an IDL Virtual Machine application from someone else and are interested in running it on your own computer, do the following:

1. Install IDL. If the application you received does not include a runtime IDL distribution or installer, you can use an IDL installer from Exelis VIS. You do not need an IDL license to run Virtual Machine applications.
2. Install the Application. Follow the application developer’s instructions to install the Virtual Machine application on your computer.
3. Run the Application. Follow the application developer’s instructions to start the application, or see Start a Virtual Machine Application.

## Steps to Create and Distribute Your Application

To create and distribute an IDL Virtual Machine Application, do the following:

1. Create your application using an IDL development license, observing the limits described in Limitations of Virtual Machine Applications. Test the application in the IDL Virtual Machine.
2. Create one or more SAVE files containing your application.
3. Provide your users with instructions for installing an unlicensed copy of IDL, or create a runtime application distribution using MAKE_RT.
4. Provide your users with instructions for installing your IDL application.
5. Provide your users with instructions for running your IDL application in the IDL Virtual Machine.

Also see Preferences for Virtual Machine Applications.