Depending on what version of the LabVIEW Development package you bought you may or may not have the Application Builder. The application builder enables you to create "executible" versions of LabVIEW programs that can be distributed as ".exe" type programs. These require that the target computer have the LabVIEW Runtime Engine installed, which is a free download. An installer is a set of files that the Application Builder can create that will bundle the LabVIEW Runtime Engine, the .exe version of your program and any support files that you define during the build process. As to the number of installs, the last time I looked it was three as Dennis mentions.
PutnamCertified LabVIEW Developer
Senior Test Engineer North Shore Technology, Inc.
Currently using LV 2012-LabVIEW 2018, RT8.5
LabVIEW Champion