Semantic search is a powerful approach when we want to retrieve results that take into account the semantic meaning of query terms, whereas lexical search relies on exact term matching and full-text search scans entire documents for occurrences of query terms. The choice of information retrieval algorithm depends on the specific use case, such as exact matching, document-heavy systems, or complex NLP-based systems. Hybrid search combines the strengths of multiple algorithms, including semantic search with either full-text or lexical search, to provide both semantic understanding and exact keyword matching. A unified system like Milvus can facilitate hybrid searches, offering improved user experience and flexibility.