contexts: The National Do Not Call Registry is a database maintained by the United States federal government , listing the telephone numbers of individuals and families who have requested that telemarketers not contact them . Certain callers are required by federal law to respect this request . Separate laws and regulations apply to robocalls in the United States .
name: National Do Not Call Registry
answers.input_text: short
answers.span_text: listing the telephone numbers of individuals and families who have requested that telemarketers not contact them
questions.input_text: what is the purpose of the national do not call registry