Test Data are data which have been specifically identified 
for use in executing test scripts, and are used to verify 
the expected results obtained.

The test data must simulate the real time user scenarios.

Thanks
Rajendra Prasad Reddy
rajendra_penumalli@yahoo.com
Hyd

Data that is used at the time of executing the Test Cases 
refers to Test Data

Eg while testing the login page

User Name: Testing
Password : Testing

Here Testing refers to the Test Data

data means information. Test data means testing the whether
the information is correcti.e variance between actual and
expected result

Test data is nothing but the input data what we are using
while conducting testing is known as Test Data.

regards
SM