you pay taxes for government for roads or cars ........etc. While you pay duty " like in free zones" for foriegn products coming to your country.

The biggest difference between the tax and duty is that duty is charged on imported goods and one can also say it is import tax. Like duty on imported car, Electronics and so on. Whereas, the simple taxes are government charges on goods or services with in the country. For example hotel services, city bridge/road repairing services and so on.