A "Show/Hide" field dependency causes a field to be dynamically displayed or hidden based on the value selected by the user in one of the picklist fields in the form.
Let us say you wanted to set up your Accompa system such that the Add Requirement page displays Dimensions field only when a user selects a hardware product from the picklist field Products.
You can achieve this using the "Show/Hide" Field Dependency in Accompa and using the following configuration: