Scandinavia is a geographic term including only Denmark, Norway and Sweden. The term Nordic countries also includes Finland and Iceland, although the terms often are used interchangeably. Greenland is geographically a part of North America, but is politically linked to the rest of the Nordic countries by being both an integral part of the Danish Kingdom and a member of the Nordic Council, a cooperative organization.

Strictly speaking, only Norway and Sweden are geographically Scandinavian, as Denmark is separated from the two by the entry to the Baltic Sea. "Fennoscandia" is a rarely used but technically accurate term for the Scandinavian mainland plus Finland, while the Jutland peninsula (the mainland portion of Denmark, but not its main centre of population) also includes part of German Schleswig Holstein. As a political and cultural term, "Nordic countries" also includes islands in the Atlantic such as Iceland, the Faroes and in most definitions Greenland, as there are long-standing political and linguistic ties. Estonia considers itself at least partially Nordic but is not always seen as such by others.

Denmark and coastal areas of Southern Norway, Iceland and Western Sweden experience only occasional frost and snow during winter. Summers in Denmark, Sweden, Norway and Finland are pleasantly warm, with day temperatures in the range 15–30°C. In the mountains and along western coasts, the weather is generally more unstable. Finland has the most stable sunny weather in summer. In general, the further inland, the larger the difference between summer and winter. While western Norway and the Atlantic Islands only see temperature differ moderately between summer and winter, in Finland the temperature occasionally drops below -20°C even in the south, with records below -50°C (-55°F) in the north – Norway's and Sweden's northern interior has equally cold winters.