Terms of service (also known as terms of use and terms and conditions, commonly abbreviated as ToS or TOS and TOU) are rules, that one must agree to abide by in order to use a service.[1] Terms of service can also be merely a disclaimer, especially regarding the use of websites.

The Terms-of-Service Agreement is mainly used for legal purposes by websites and internet service providers that store a user’s personal data, such as e-commerce and social networking services. A legitimate terms-of-service agreement is legally binding and may be subject to change.