Jim Crow laws were laws passed on the state and local levels in the Reconstruction period in the southern United States. Following the Emancipation Proclamation and the Civil War, Jim Crow laws enforced segregation and removing the rights from blacks. One major right that was degraded through these laws was the right to vote.
Many southern states implemented literacy tests at the voting booth. Blacks who were the first generation removed from slavery were disproportionally unlikely to be literate as education was not provided for slaves. Some states allowed an oral test if a potential voter was not literate. If these people could understand a statement read to them, they would be allowed to vote. Many illiterate whites passed this test and many illiterate blacks failed due to racism by the test administrators.
Many southern states also implemented property requirements, meaning that a voter must own property in order to be allowed to vote. Many blacks during Reconstruction did not have enough money to purchase property as a result of their slavery.
Some states implemented grandfather clauses, where people who were not literate and were not property owners could still vote if their fathers or grandfathers had voted prior to 1867, which applied to almost no African Americans.