Adobe ACROBAT FORMS JAVASCRIPT OBJECT Specification page 51

all variables with "xyz_". This will prevent collisions with other persistent global variable
names throughout the documents.
Note that global variables that are persistent are recorded in the plug-in level glob.js file upon
Plug-in folder level
application exit and re-loaded at application start. See the section on scripts
for more details.
Acrobat Forms - JavaScript Object Specification 51