Floating fields are objects that support the merging of text, numeric values, run-time properties, and scripting within a text object when the form is rendered. You can insert floating fields into text objects only.
You can bind floating fields to a data source to display specific text or numeric values. For example, you can insert a floating field to render individual customer names in the introductory greeting of a form letter. The floating field appears as a TextField object, as shown in this example.
Note:
When merging floating fields with data, keep in mind that floating fields cannot span pages. Floating fields are also non- interactive in Acrobat 6.0.2 and Acrobat 7.0.5-compatible forms.
You must set the properties of the floating field object independently of setting the properties of the text object. By default, floating field objects are set to Hidden (Exclude from layout) in the Presence list.
2.
Place your cursor on the line where you want LiveCycle Designer ES to insert the floating Text Field object.
4.
To set the properties of the Floating Field, click the Floating Field marker inside the Text object, and then select options as needed. It is good practice to rename the floating Text Field object and specify the necessary binding.
See also 

To insert a floating field