Phonological change refers to the evolution of sounds in a language over time. This can occur due to various factors, including social interaction, geographical movement, and language contact. As speakers adapt their pronunciation, certain sounds may become more similar or different, leading to shifts in phonetic patterns. One common example of phonological change is vowel shift, where the pronunciation of vowels changes systematically. A historical instance is the Great Vowel Shift in English, which significantly altered the way long vowels were pronounced between the 15th and 18th centuries. Such changes can impact the overall structure and comprehension of a language.