What supreme court decision upheld the legality of segregation so long as "separate but equal" facilities were provided?

Plessy v. Ferguson, 163 U.S. 537 (1896),was a landmark decision of the U.S. Supreme Court issued in 1896. It upheld the constitutionality of racial segregation laws for public facilities as long as the segregated facilities were equal in quality – a doctrine that came to be known as "separate but equal".This legitimized the many state laws re-establishing racial segregation that had been passed in the American South after the end of the Reconstruction Era (1865–1877). The decision was handed down by a vote of 7 to 1, with the majority opinion written by Justice Henry Billings Brown and the lone dissent written by Justice John Marshall Harlan. This is from Wikipedia so please put in your own words.

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