Discriminatory voting practices in Black history refers to various laws, policies, and practices that were designed to prevent African Americans from exercising their right to vote. These practices were prevalent in the United States, particularly in the southern states, and were used to disenfranchise and suppress the Black vote. Some of the most common discriminatory voting practices in Black history include:

1. Poll Taxes: Poll taxes were a fee that individuals had to pay in order to vote. This practice disproportionately affected African Americans, as many were unable to afford the tax.

2. Literacy Tests: Literacy tests were used to determine an individual's ability to read and write. These tests were often administered in a discriminatory manner, with African Americans being subjected to more difficult tests than white voters.

3. Grandfather Clauses: Grandfather clauses allowed individuals to bypass literacy tests and poll taxes if their ancestors had been eligible to vote before the Civil War. Since many African Americans' ancestors had been enslaved and therefore ineligible to vote, this clause effectively disenfranchised Black voters.

4. Voter Intimidation: Black voters were often subjected to intimidation tactics, such as threats of violence or economic retaliation, in order to prevent them from voting.

5. Gerrymandering: Gerrymandering is the practice of manipulating voting district boundaries to benefit a particular political party. This practice has been used to dilute the voting power of African American communities.

These discriminatory voting practices persisted for many years and were used to suppress the political power of African Americans. The struggle to overcome these barriers to voting has been a central part of the ongoing fight for civil rights and equality in the United States.