BERTopic is a python library for transformer-based topic modeling, useful in various NLP applications like document tagging and content organization.BERTopic consists of 6 core modules for topic modeling customization: Embeddings, Dimensionality Reduction, Clustering, Vectorizers, c-TF-IDF, and Representation Model.Using sentence-transformer models, BERTopic converts text into semantic embeddings, with options like 'all-MiniLM-L6-v2' and 'BAAI/bge-base-en-v1.5'.Dimensionality Reduction techniques like UMAP are vital for reducing high-dimensional embeddings to improve cluster formation.Clustering involves grouping text documents into topics using models like HDBSCAN and K-Means based on semantic similarity.Vectorizer options like CountVectorizer help create matrix representations of terms in documents to improve topic analysis.c-TF-IDF focuses on reducing frequently encountered words across clusters by evaluating keyword importance at the cluster level.Representation Model leverages semantic similarity to refine topic keywords, offering options like KeyBERTInspired for better topic descriptions.Practical application on Apple financial news data demonstrates the effectiveness of BERTopic modules in identifying meaningful topics.Experimentation and customization of each BERTopic module help improve topic representations and reveal insights from textual data.BERTopic's versatility and customizable modules make it a powerful tool for transformer-based topic modeling in NLP tasks.