Languages are primarily classified using two major systems: genetic (or genealogical) classification and typological classification.
Genetic (or Genealogical) Classification: This system categorizes languages into families based on their historical and evolutionary relationships. It traces languages back to a common ancestor, known as a proto-language. For example, the Romance languages (such as French, Spanish, and Italian) all derive from Latin.
Typological Classification: This classification is based on the structural features and characteristics of languages, such as word order, phonetic systems, and grammatical structures. It does not consider historical relationships but rather categorizes languages based on similarities and differences in their linguistic features.
Additional approaches like areal classification may also be used, which focus on languages' geographical distribution and influence due to proximity source.
Here's a visual representation of language classification: