embedding
**Embeddings** are **dense vector representations that capture semantic meaning** — transforming text, images, or data into fixed-dimensional numerical vectors where similar items are close together and dissimilar items are far apart, enabling semantic search, clustering, classification, and recommendation systems.
**What Are Embeddings?**
- **Format**: Fixed-length float arrays (e.g., 384, 768, 1536 dimensions).
- **Property**: Semantically similar inputs produce similar vectors.
- **Distance**: Cosine similarity or Euclidean distance measures relatedness.
- **Models**: E5, BGE, OpenAI ada-002, Cohere embed, Jina embeddings.
**Types of Embeddings**
- **Word Embeddings**: Word2Vec, GloVe — individual word vectors.
- **Sentence Embeddings**: E5, BGE, all-MiniLM — full sentence meaning.
- **Document Embeddings**: Longer text representations.
- **Multimodal**: CLIP — shared space for text and images.
**Applications**
- **Semantic Search**: Find relevant documents by meaning, not just keywords.
- **RAG**: Retrieve context for LLM generation.
- **Clustering**: Group similar items automatically.
- **Classification**: Use as features for downstream ML models.
- **Recommendation**: Find similar products, content, or users.
**Top Models (2025)**
- **OpenAI text-embedding-3-large**: 3072d, strong general purpose.
- **BGE-M3**: Multilingual, multi-granularity, open-source.
- **E5-Mistral-7B**: Instruction-tuned, state-of-the-art on MTEB.
- **Jina Embeddings v3**: 8K context, multilingual.
- **Cohere Embed v3**: Strong multilingual with compression.
Embeddings are **the bridge between human language and machine computation** — enabling AI systems to understand meaning, find relevance, and make connections across vast amounts of unstructured data.