These are very specific to a particular unit. The basic functionality of the unit is to be understood based on the requirements and the design documents. Generally, Design document will provide a lot of information about the functionality of a unit. The Design document has to be referred before UTC is written, because it provides the actual functionality of how the system must behave, for given inputs.
For example, In the Online shopping application, If the user enters valid Email id and Username values, let us assume that Design document says, that the system must display a product details and should insert the Email id and Username in database table. If user enters invalid values the system will display appropriate error message and will not store it in database.

 Login Screen Test Conditions for the fields in the Login screen

 Email-It should be in this format (For Eg clickme@yahoo.com).
Username – It should accept only alphabets not greater than 6.Numerics and special type of characters are not allowed.

 Test Prerequisite: The user should have access to Customer Login screen form screen

 Negative Test Case:
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Positive Test Case:
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