The Big Text Input was former known as the option Area.
The Big Text Input works very simillar to the Small Text Input, but is ment for longer inputs.
For example you can let the customer insert a message, a question, a caption text, ...
Presentation in the frontend
Settings in the backend
You can restrict the input by using the setting Min. string length and/or Max. string length.
Furthermore you can set a default value which is shown as the initial value inside the input field, you can change if it's shown as a default value (Costumer has to delete it if he wants to write something else) or as a placeholder (Greyed-out, disappears when the customer clicks into the field) with the setting Placeholder.