One of the cornerstone features of an Adaptive Interviews (SmartForms) is the ability to hide and/or display questions based on user responses. This dynamic process is configured using "conditions", which are defined on individual questions or on a whole page.
The behavior of these conditions is to generally make a question or page "inactive", which is to say it is both invisible and not relevant to the final outcome. allows you to control whether your conditions renders the target ‘inactive’ or simply 'invisible'. An invisible question is hidden but still deemed relevant for any dependencies such as calculations and future conditions.
Conditions on multiple choice answers
Data source conditions and parents
Conditions vs. Rules
Finish page conditions
Make a document conditional
Same page conditions
Visible conditions vs active conditions