There have been 8 major federal laws known as "Civil Rights Acts" over the years, the most famous of which is the Civil Rights Act of 1964.
There were Civil Rights Acts enacted in 1866, 1871, 1875, 1957, 1960, 1964, 1968 and 1991.
The 1964 Act is the most important of these because it outlawed more types of discrimination than any of the others (outlawed all discrimination on the basis of race, religion, sex and some other factors by any governments and in any public accomodations that were part of interstate commerce).
Another important civil rights law that is not called a Civil Rights Act was the Voting Rights Act of 1965.
There have been 8 major Civil Rights Act.