Guarantees of certain rights, such as freedom of speech and right of assembly. In the United States, these rights are upheld by the Constitution (although they are also frequently challenged in society as well as in the courts).
The rights or freedoms of an individual in a society. In the U.S. these include the right to free expression, freedom of movement and association, freedom from unwarranted search and seizure, and freedom of religion.
Civil liberties is the name given to freedoms that protect the individual from government. Civil liberties set limits for government so that it can not abuse its power and interfere with the lives of its citizens. See also civil rights and human rights.