Tampering can refer to many forms of sabotage but the term is often used to mean intentional modification of products in a way that would make them harmful to the consumer. This threat has prompted manufacturers to make products that are either difficult to modify or at least difficult to modify without warning the consumer that the product has been tampered with. Since the person making the modification is typically long gone by the time the crime is discovered, many of these cases are never solved.
The crime is often linked with attempts to extort money from the manufacturer, and in many cases no contamination to a product ever takes place. Fraud is sometimes handled as a matter of civil law, but actual modification of products is almost always a matter of criminal law.