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 A Precondition is like defining the step "0" for your tests. This is very useful in many use cases where you have to start by doing exactly the same thing. For example, if you are going to do something on a system, you most probably have to authenticate first, right? But sometimes, you have to do several things  (e.g., restore the DB, authenticate) before going through your Test steps. And each of those things may be done and used independently, i.e., some Tests may require just restoring the DB, another may require just to authenticationauthenticate, and others may require both things or more. 

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Precondition Types

Pre-Conditions Preconditions Types must be the same Kind of the Type of the Test they are associated with, so they can be Manual or Automated.

• Manual Type Pre-ConditionsSteps Kind Type Preconditions: Conditions to be executed by the user before starting the Associated associated Test.Generic Type
• Pre-ConditionsUnstructured Kind Type Preconditions: Conditions to be executed by the external tool before starting the Associated associated Test.
• Cucumber Type Pre-ConditionsGherkin Kind Type Preconditions: Cucumber Background Gherkin clauses to be executed before starting the associated Scenarios.

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