Test Data is nothing but the client or customer requiremnts.

It is prepared by Client or Customer, wht r there needs or 
reqirements.

hi 

which real data we going to use in our testing is called
test data.

Test Data is the input data which we give to check the 
feature of an app to know whether its working correctly or 
not.

The input data could be valid for positive test cases and 
invalid for negative test cases

Test data id the data which is required for the testing of
the functionality of the feature.

Test Data is prepared on the following approach:
1. On the Motivation of the feature.
2. According to the SRS.
3. According to the USE Case.

For Preparation of the test Data there are not any specific
method or guideline, it is depend on the situation,
environment and above all on the organization.

Aman
aman.testing@gmail.com