When developing a search interface, sometimes allowing the user to select a range of values is appropriate.  This is often presented as a drop-down list as shown below:

This allows the user to select from a dropdown list instead of entering a value directly.  The expectation when choosing 1-1000 is that the system should return results for any records with values for "range test" between the user's chosen value, shown as 1-1000 above.

To create this type of field, go to Fields, and click New.  Choose Range under field type as shown here:

The Range Values option is used to build the search form drop-down list.  It should be provided in the following format

Start Value-End Value, Label;Start Value-End Value, Label;Start Value-End Value, Label;

For example, if we created a field called "SqFt" and entered the following values

1-100,Small;101-200,Medium;201-300,Large

This would produce a drop-down list with 3 values, Small, Medium and Large.  Users choosing those values would find rows in your database with values in the "sqft" column that fell within the chosen range.