Duty
A legal obligation to conform one's conduct to a standard of reasonable care for the protection of others against unreasonable risks.
Special relationships (carrier-passenger, innkeeper-guest, employer-employee, parent-child, custodian-ward) create affirmative duties to act. Landowners owe varying duties to trespassers, licensees, and invitees under the traditional rules; many states have collapsed these into a single duty of reasonable care.