Using the cfparam tag with the name attribute is one way to clearly define the variables that a page or a custom tag expects to receive before processing can proceed. This can make your code more readable, as well as easier to maintain and debug.

For example, the following cfparam tags indicate that this page expects two form variables named StartRow and RowsToFetch:

<cfparam name="Form.StartRow">
    <cfparam name="Form.RowsToFetch">

If the page with these tags is called without either one of the form variables, an error occurs and the page stops processing. By default, ColdFusion displays an error message; you can also handle the error as described in Handling Errors.