What tools do linguists use to classify and compare languages?

Linguists use a variety of tools and methods to classify and compare languages, primarily based on their similarities and differences. Some of the key tools and methods include:

1. Comparative Method: This is one of the most essential techniques. It involves comparing languages to identify common features, shared ancestry, and historical relationships. Linguists look for cognates (words that have a common origin) and phonological, morphological, syntactic, and semantic patterns. Through systematic sound changes and regular patterns, linguists can reconstruct proto-languages, which are hypothetical ancestral languages.
2. Phylogenetic Trees: Linguists create these trees to visually represent the historical relationships between languages. Languages that share a more recent common ancestor are placed closer together. This is similar to how biological evolution is depicted in phylogenetic trees.
3. Lexical and Structural Analysis: Lexical analysis involves comparing vocabulary across languages. Linguists often look for shared roots, prefixes, or word forms. Structural analysis focuses on comparing the grammar (syntax, morphology, etc.) of different languages to identify common features.
4. Language Typology: Linguists use typology to classify languages based on their structural features, like word order, morphology, and phonological patterns. It helps group languages into types based on common grammatical or syntactical traits (e.g., SVO or SOV word order).
5. Glottochronology: This method tries to estimate the time of divergence of languages from a common ancestor by analyzing the rate of vocabulary change. It uses statistical models to predict how languages evolve over time.
6. Corpus Linguistics: Large databases of language (corpora) are used to analyze the frequency and distribution of words, phrases, and grammatical structures. This method is useful for studying both synchronic (contemporary) and diachronic (historical) language data.
7. Phonetic and Phonological Analysis: This involves the detailed study of sounds in languages, using tools such as the International Phonetic Alphabet (IPA) to transcribe and compare sounds. Phonological patterns help to classify languages and understand sound changes over time.
8. Fieldwork and Ethnographic Methods: Linguists often conduct fieldwork, interviewing native speakers, recording oral traditions, and gathering linguistic data firsthand. This helps in the documentation and comparison of less-studied or endangered languages.
9. Genetic Classification Systems: This involves grouping languages into families based on their historical relationships. For example, the Indo-European language family, which includes languages like English, Spanish, and Hindi, is one of the most well-known. These families are further broken down into branches.
10. Digital Tools and Software: Tools like LexStat or TreeMix can help analyze linguistic data, model language relationships, and even visualize language phylogenies. Linguists may also use software like ELAN or Praat to analyze phonetic data and transcriptions.

These tools and methods are combined to build models of how languages are related, how they change over time, and how they can be classified into families or types.