This paper explores how people in different parts of Bangladesh talk differently from each other. The study pays special attention to the unique sounds in their dialects compared to the standard Bangla language. The main goal of the research is to understand why these sounds change from one dialect to another. The researchers collected data from 70 participants coming from 20 regions of Bangladesh, who were fluent in their regional dialects and studied it carefully. By employing semi-structured interviews, IPA transcription, and thorough verification processes, this study ensures the accuracy and reliability of its findings and discussion, contributing valuable insights into the phonological diversity of Bangladeshi dialects and their socio-linguistic significance. The authors found 13 phonological variations or patterns among the dialects of different regions of Bangladesh. Each type of change is explained with clear examples to make it easier to understand. The research contributes significantly to the understanding of socio-linguistic diversity in Bangladesh by providing experimental evidence of phonological variation and its determinants. It also lays the groundwork for future research on dialects and their relationship with the standard language. This study will bring up a greater appreciation for Bangladesh's linguistic diversity and encourage further research into language variation and change.