Final answer:
The summer of 1964, also known as Freedom Summer, refers to a campaign where students from the North went to Mississippi to register black voters. This campaign aimed to challenge the disenfranchisement of African Americans and made progress in registering African American voters in Mississippi.
Step-by-step explanation:
The summer of 1964, during which white and black students from the North went to Mississippi to assist in registering black voters, is commonly referred to as Freedom Summer. This campaign aimed to challenge the disenfranchisement of African Americans in the Deep South and involved organizing citizenship schools and voter registration exams. Participants faced threats and violence, but their efforts helped bring attention to the issue of voting rights and made progress in registering African American voters in Mississippi.