RainbowCrack is a general-purpose implementation of Philippe Oechslin's faster time-memory trade-off technique. In short, the RainbowCrack tool is a password cracker. A traditional brute force cracker try all possible plaintexts one by one in cracking time. It is time consuming to break complex password in this way. The idea of time-memory trade-off is to do all cracking time computation in advance and store the result in files so called "rainbow table". It does take a long time to precompute the tables. But once the one time precomputation is finished, a time-memory trade-off cracker can be hundreds of times faster than a brute force cracker, with the help of precomputed tables.