Slavic peoples are based on Slavic languages that belong to the Indo-European language family. Modern Slavs are divided into 3 groups: eastern, southern and western. Slavic languages are especially close to the group of Baltic languages, even a special Slavic-Baltic community (2—1 millennia BC) stands out. In even more ancient times, Slavic languages (4—3 millennia BC) were most likely closely associated with Iranian languages.