How you are taxed will depend on how long you are staying in Finland. If you are a foreign national and working in Finland, you will have to get a tax card from your local tax office. A useful source of tax advice for workers moving to Finland from abroad is the In To Finland service.
Taxes in Finland are slightly higher than in EU countries on average. The government uses tax revenue to maintain a high standard of public services, including education, health care, social security as well as care for children and the elderly.
Your local tax office is called a ‘verotoimisto’. Tax offices determine tax rates for earned income and capital gains, for example.
The Ministry of Finance website also contains useful information.