Google apps script: how to persist data in spreadsheet between different function calls?

Question

In a Google spreadsheet using the Script Editor, I do function calls, but I am not quite sure if the best way to store persistant data (data that I will continue to use) is

Answer 1

Persistent data can be stored using the Class ScriptProperties:

http://code.google.com/googleapps/appsscript/class_scriptproperties.html

All values are stored as a string and will have to be converted back with the likes or parsInt or parseFloat when they are retrieved.

JSON objects can also be stored in this manner.