7. What is a Cracker?

Traditionally, a Cracker was a person who obtained unauthorised access to a computer system using a password which had been produced by trying likely variants, usually by using software tools and/or system data to produce passwords with a better than random chance of being valid. Once access has been gained to an interactive computer, the chances of gathering useful data are greatly increased and there are increased risks for the entire system, not simply the first account to be accessed.

Your password is stored on the system in encrypted form, that is, the computer only knows a coded version of each password. When you log in, the password you type is encrypted in the same way and your login is allowed if the result matches. It is not possible to obtain the original password direct from the encrypted version so some form of trial and error is needed to "crack" the code.

With faster processors and cheap disk storage, it became possible to use very sophisticated software to try many passwords and the word "cracker" was more often used to describe this software. However, systems can impose a time delay when, say, three wrong passwords have been given, so any speed advantage is lost. In fact, it is now a lot easier to use social engineering to get the right password first time, and bank details for a few people are more use to a criminal than limited access to a powerful computer.

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