A cease and desist letter (also known as a notice to stop letter or a demand letter) is a legal document used to notify a person or party of your legal notice requesting them to stop a behaviour or action that offends your traditional liberties.
In many cases, a cease and desist letter is the primary step you will take when you wish to stop unwanted activity. A cease and desist letter most frequently has a threat included that lets the other party know that you may take lawful action if they do not cease and desist whatever they are doing.