The maturity test is a written assignment that is part of your degree and relates to your thesis.
In a lower university degree (bachelor), the maturity test demonstrates your familiarity with the field of your thesis as well as your proficiency in Finnish or Swedish.
In a higher university degree (master), the maturity test also demonstrates your familiarity with the field of your thesis and your proficiency in Finnish or Swedish. If you have already demonstrated your language proficiency in the maturity test for your lower degree, you do not need to demonstrate it again in the maturity test for your higher degree.
The format of the maturity test varies between degree programmes. Check the requirements for your degree in the Peppi study guide.
The maturity test is regulated by Government Decree 794/2004 (on Finnish).