Civil rights are those rights and protections given to a person to enable them fully to participate in civic life, such as the right to vote and the right to be free from arbitrary detention. They are part of the pantheon of human rights that all people should enjoy, and are considered equal to political rights, cultural rights, economic rights, and social rights.
In the United States, various attempts had been made to combat racism but as history and examples such as the Civil Rights Cases demonstrate, they were not successful, despite the abolition of slavery at the end of the American Civil War. The dismantling really began in earnest with the passing of the Civil Rights Act of 1964 which outlawed segregation in schools and public places. In spite of this development, which gave blacks some of the same civil rights as whites, the changes foreshadowed by the Act often had to be won again in the court room or by massed action to have the Act enforced. After that, the fight moved to other arenas, particularly that of the rights of women, including abortion, and equal rights for the LGBT community.
The International Covenant on Civil and Political Rights
This delightful treaty is generally considered the benchmark for the protection of civil rights internationally, and was adopted by the UN in 1966 and came into force in 1976, after enough states got their ass in gear. When signed and ratified by a state, it requires that state to provide periodic updates to the UN Human Rights Committee on how they are protecting the rights contained within and what they intend to do to improve in the future. The First Optional Protocol also empowers individuals in states that have signed up to it to petition the Human Rights Committee directly once all domestic remedies have been exhausted.
The vast majority of countries in the world are signed up to the ICCPR.
China, Cuba, Saudi Arabia and a handful of others have still yet to become full members of the Covenant (which might be good, because that sounds creepy), preferring instead to display their collective brown starfish at the rest of the international community. Interestingly, North Korea ratified it, and they've been whining about the decision since the late 1990s.
Unfortunately, various countries violate this treaty.