Anyone who has ever watched an American crime movie or television show can practically recite the Miranda warning by heart, even if they don’t know its official name.
You have the right to remain silent. Anything that you say or do can be used against you. You have the right to an attorney. If you cannot afford one, one will be provided to you. Do you understand these rights as I have read them to you?
The basic idea behind the Miranda warning is to provide someone being arrested with information about their constitutional rights against compelled self-incrimination (Fifth Amendment) during a custodial situation and to reassure them of their right to an attorney (Sixth Amendment).
This warning stems from a 1966 Supreme Court case, Miranda v. Arizona, where a kidnapping and rape suspect, Ernesto Miranda, confessed to the crime without the benefit of a lawyer and without being fully informed of his rights to not self-incriminate. Today, all American police officers must recite some version of the Miranda warning while taking someone into custody due to the Supreme Court’s landmark 5-4 decision.