Here's the summary for the wikipedia article you mentioned in your comment:

A disclaimer is generally any statement intended to specify or delimit the scope of rights and obligations that may be exercised and enforced by parties in a legally recognized relationship. In contrast to other terms for legally operative language, the term disclaimer usually implies situations that involve some level of uncertainty, waiver, or risk. A disclaimer may specify mutually agreed and privately arranged terms and conditions as part of a contract; or may specify warnings or expectations to the general public (or some other class of persons) in order to fulfill a duty of care owed to prevent unreasonable risk of harm or injury. Some disclaimers are intended to limit exposure to damages after a harm or injury has already been suffered. Additionally, some kinds of disclaimers may represent a voluntary waiver of a right or obligation that may be owed to the disclaimant.

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