What is a language family?
A language family is a group languages that are related in some way, they developed from a common historic ancestor, referred to as protolanguage (proto- means 'early' in Greek). We can know the ancestral language comparing the languages. It will help us to define the family status of many languages. Most languages on the earth belong to language families. Language families can be subdivided into smaller units called branches.
How do linguists establish relationships among languages?
Let's research the Romance languages, establishing relationships among languages. For example, Italian a descendant of Latin, a language that was spoken in Italy two thousand years ago, and one which left a great number of written documents. The Roman conquest helped spread Latin throughout Europe where it eventually developed into regional dialects. When the Roman Empire collapsed, these regional dialects evolved into the modern Romance languages that we know today: French, Italian, Portuguese, Spanish, and others. These languages form the Romance branch of the Indo-European language family. Let’s look at the word-equivalents of 'water' in three Romance languages and see the similarities.
| Italian | aqua | | Spanish | aqua | | Portuguese | aqua |
What if the ancestral language left no records?
In case with Romance languages is unusually easy because their common ancestor — Latin — left many written documents. If the ancestral language left no records linguists look at similarities among the modern descendants to establish common origins. Let’s take a look at these examples: | English | water | | German | wasser | | Danish | vand |
| Russian | voda | | Polish | woda | | Czech | voda |
It is obvious that word for 'water' looks very similar within each group, but not so similar across groups. Languages of the first group belong to the Germanic branch of the Indo-European language family. Languages of the second group belong to the Slavic branch. Although there are no written records of the ancestral *Proto-Germanic or *Proto-Slavic languages, scientists have to assume that these two ancestral languages must have existed, just like Latin did.
Where do these mystery languages belong?
Here are three more equivalents for 'water'.| Latvian | udens | | Albanian | uje | | Basque | ur |
Judging from dissimilarity of the words they do not refer to any previous branches above. Latvian belongs to the Baltic branch of the Indo-European language family, Albanian has no close relatives and does not belong to any branch within the Indo-European language family, and Basque does not belong to any language family at all. In fact, it is a language isolate, i.e., a language that cannot be reliably assigned to any family.
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