The TestDaF exam consists of four parts: 

Reading Comprehension (with 3 different texts)
Listening Comprehension (with 3 different texts)n
Written Expression and Oral Expression (with 4 different tasks each).

The examination results are assigned to one of three levels in all four examination parts:

TestDaF level 3 (TDN 3)
TestDaF level 4 (TDN 4)
TestDaF level 5 (TDN 5)

Target groups of the TestDaF are

• Students who wish to study in Germany and need proof of their German language skills for this purpose
• Academics who are planning a stay at a university in Germany and want to check their language level
• Students who come to Germany to study through programs of the European Union and want to acquire a qualified language certificate at the end of their stay.

Further information on the test as well as hints and tips for preparing for the exam can be found at:https://www.testdaf.de/.