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RainbowCrack is the name of a computer program which generates rainbow tables to be used in password cracking. RainbowCrack differs from "conventional" brute force crackers in that it uses large pre-computed tables called rainbow tables to reduce the length of time needed to crack a password drastically. RainbowCrack was developed by Zhu Shuanglei, and implements an improved time-memory trade-offcryptanalysis attack which originated in Philippe Oechslin's Ophcrack.
As RainbowCrack's purpose is to generate rainbow tables and not to crack passwords per-se, some organizations have endeavored to make RainbowCrack's rainbow tables available free over the internet.
