Anyone considering a move to Greece should note that there is a difference between a visa and a permit. A visa allows entry into the country for a specific purpose, such as travel or study, and a permit allows an expat to live and work in the country.
Non-EU citizens will most likely need a visa for Greece, while citizens from EU and Schengen countries, as well as certain others like the US and Canada, can stay as tourists for up to 90 days within a 180-day period.
In Greece, work permits and residence permits are not separate documents. Expats from outside of the EU who have been granted permission to enter the country on a work visa must then apply for a permit which enables them to live and work in Greece.