MicroRNAs (miRNAs) are small non-coding RNA molecules that play important roles in the regulation of gene expression at the post-transcriptional level. They are typically around 22 nucleotides in length and can bind to messenger RNAs (mRNAs) to inhibit their translation or promote their degradation. Research in the field of microRNA focuses on understanding the role of these small regulatory molecules in various biological processes, such as development, differentiation, and disease. MicroRNAs have been implicated in a wide range of diseases, including cancer, cardiovascular disease, and neurodegenerative disorders, making them potential targets for therapeutic intervention. Studies in this area often involve identifying differentially expressed miRNAs in disease states, elucidating the mechanisms by which they regulate gene expression, and investigating their potential as biomarkers or therapeutic targets. With the advancement of high-throughput sequencing technologies, researchers are able to study miRNAs on a large scale and uncover their complex regulatory networks in cells and tissues.