Countries where at least 60% of the population is Roman Catholic
Countries where at least 50% of the population is Christian
Countries where the mean temperature is less than 10 degrees Celcius according to the Tyndall Centre of Climate Change Research.
Eastern Europe according to EuroVoc.
Emerging economies as defined by the International Monetary Fund (IMF).
Countries where English is spoken as a first language by the majority of the population.
Member states of the European Union.
European Union countries that use the Euro as their sole currency.
Countries scoring over 100 in the 2013 failed states index.
Countries previously colonised by Great Britain according to the CIA World Factbook.
Countries previously colonised by France according to the CIA World Factbook.
Countries previously colonised by Spain according to the CIA World Factbook.
Modern day countries that were at one time part of Yugoslavia.
The Group of 7 is a meeting of finance ministers and central bank governments of 7 of the largest advanced economies. This group was previously known as the Group of 8 before Russia was expelled over the 2014 crisis in Crimea.
Countries where public debt is over 60% of GDP.
Countries that are both high income and members of the Organisation of Economic Co-operation and Development according to the World Bank.
Hot countries 120
Countries where the mean temperature is more than 20 degrees Celcius according to the Tyndall Centre of Climate Change Research.
Island countries 105
Countries that are on islands, rather than continents.
Military bases located outside their country's borders. For instance, Akrotiri is a UK military base in Cyprus.
Countries belonging to the North Atlantic Treaty Organization, an alliance created to counter the Soviet and now Russian military threat.
Countries with populations that are the least inclined to say they are religious according to Gallup Global Religiosity Index of 2012
Members of the Organisation of Petroleum Exporting Countries
Countries with populations that are the most inclined to say they are religious according to Gallup Global Religiosity Index, 2012
Southern Europe according to EuroVoc.
Countries where there are more tourists in a given year than the resident population.
The United Kingdom and its dependences and territories.
Areas with no permanent population.
Western Europe according to EuroVoc