Language
Montenegrin is the official language of Montenegro, but Serbian, Croatian, Bosnian, and Montenegrin are essentially identical so nearly every person speaks the same language although it may be called any number of things (most commonly known as Serbo-Croatian in English). In addition to these languages, Montenegrin is also closely related to the other Southern Slavic languages, including Slovenian. Montenegrin is often times written in both the Latin script and Cyrillic script, but is moving more towards using the Latin script.
English is a growing second language in Montenegro and many young people speak at least some English. However, learning second languages in Montenegro is a relatively new idea and few people speak a second language, especially the country's adult population.
Religion
Most of Montenegro's population is Orthodox, although there is a significant Muslim minority. Most of the Muslims are ethnic Albanians or Bosniaks (Muslim Bosnians).
Orthodoxy is a Christian religion that claims to be the most loyal to the Christian faith and religion as it was described by Jesus and the Gospels in the New Testament. Christianity, including Orthodoxy, was founded after the death of Jesus in about 30-33 AD; various branches of Orthodoxy were officially recognized by governments long before Catholicism was recognized in the Roman Empire.