A pair of words like kátur and gátur that differ only in one "phone" is called a minimal pair.
Here are examples of the phonemes /r/ and /l/ occurring in a minimal pair:rip
In the field of comparative linguistics the comparison of phones is important in efforts to trace connections between languages. Comparative linguistics is the study of similarities and differences between languages, in particular the comparison of related languages with a view to reconstructing forms in their lost parent languages.
Related reading: Glossary of Linguistic Terms; Phoneme Study Pinpoints Origin of Modern Languages; Comparative Linguistics