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What are vector embeddings?

Vector embeddings are numerical representations that capture the relationships and meaning of words, phrases and other data types. Through vector embeddings, essential characteristics or features of an object are translated into a concise and organized array of numbers, helping computers rapidly retrieve information. Similar data points are clustered closer together after being translated into points in a multidimensional space.

Used in a wide range of applications, especially in natural language processing (NLP) and machine learning (ML), vector embeddings help manipulate and process data for tasks such as similarity comparisons, clustering and classification. For example, when looking at text data, words such as cat and kitty convey similar meanings despite differences in their letter composition. Effective semantic search relies on precise representations that adequately capture this semantic similarity between terms.

Are embeddings and vectors the same thing?

The terms vectors and embeddings can be used interchangeably in the context of vector embeddings. They both refer to numerical data representations in which each data point is represented as a vector in a high-dimensional space.

Vector refers to an array of numbers with a defined dimension, while vector embeddings use these vectors to represent data points in a continuous space.

Embeddings refer to expressing data as vectors to capture significant information, semantic links, contextual qualities or the organized representation of data learned via training algorithms or machine learning models.

Types of vector embeddings

Vector embeddings come in a variety of forms, each with a distinct function for representing different kinds of data. The following are some common types of vector embeddings:

  • Word embeddings. Word embeddings are vector representations of individual words in a continuous space. They're frequently used to capture semantic links between words in tasks such as sentiment analysis, language translation and word similarity.
  • Sentence embeddings. Vector representations of complete sentences are called sentence embeddings. They're helpful for tasks including sentiment analysis, text categorization and information retrieval because they capture the meaning and context of the sentence.
  • Document embeddings. Document embeddings are vector representations of whole documents, such as articles or reports. Typically used in tasks such as document similarity, clustering and recommendation systems, they capture the general meaning and content of the document.
  • User profile vectors. These are vector representations of a user's preferences, actions or traits. They're used in customer segmentation, personalized recommendation systems and targeted advertising to gather user-specific data.
  • Image vectors. These are vector representations of visual items, such as pictures or video frames. They're used in tasks such as object recognition, image search and content-based recommendation systems to capture visual features.
  • Product vectors. Representing products or items as vectors, these are used in product searches, product classification and recommendation systems to gather features and similarities between products.
  • User profile vectors. User profile vectors represent a user's preferences, actions or traits. They're used in user segmentation, personalized recommendation systems and targeted advertising to gather user-specific data.

How are vector embeddings created?

Vector embeddings are generated using an ML approach that trains a model to turn data into numerical vectors. Typically, a deep convolutional neural network is used to train these types of models. The resulting embeddings are often dense -- all values are non-zero -- and high dimensional -- up to 2,000 dimensions. Popular models such as Word2Vec, GLoVE and BERT convert words, phrases or paragraphs into vector embeddings for text data.

The following steps are commonly involved in the process:

  1. Assemble a large data set. A data set capturing the specific data category for which embeddings are intended -- whether it pertains to text or images -- is assembled.
  2. Preprocess the data. Depending on the type of data, the cleaning, preparation and data preprocessing involves eliminating noise, resizing photos, normalizing text and carrying out additional operations.
  3. Train the model. To identify links and patterns in the data, the model is trained using the data set. To reduce the disparity between the target and predicted vectors, the pretrained model's parameters are changed during the training phase.
  4. Generate vector embeddings. After training, the model can convert fresh data into numerical vectors, presenting a meaningful and structured representation that effectively encapsulates the semantic information of the original data.

Vector embeddings can be made for a wide range of data types, including time series data, text, pictures, audio, three-dimensional (3D) models and video. Because of the way the embeddings are formed, objects with similar semantics will have vectors in vector space that are close to one another.

Where are vector embeddings stored?

Vector embeddings are stored inside specialized databases known as vector databases. These databases are high-dimensional mathematical representations of data features. Unlike standard scalar-based databases or independent vector indexes, vector databases provide specific efficiencies for storing and retrieving vector embeddings at scale. They offer the capacity to effectively store and retrieve huge quantities of data for vector search functions.

Vector databases include several key components, including performance and fault tolerance. To ensure that vector databases are fault-tolerant, replication and sharding techniques are used. Replication is the process of producing copies of data across numerous nodes, whereas sharding is the process of partitioning data over several nodes. This provides fault tolerance and uninterrupted performance even if a node fails.

Vector databases are effective in machine learning and artificial intelligence (AI) applications, as they specialize in managing unstructured and semi-structured data.

Applications of vector embeddings

There are several uses for vector embedding across different industries. Common applications of vector embeddings include the following:

  • Recommendation systems. Vector embeddings play a crucial role in the recommendation systems of industry giants, including Netflix and Amazon. These embeddings let organizations calculate the similarities between users and items, translating user preferences and item features into vectors. This process aids in the delivery of personalized suggestions tailored to individual user tastes.
  • Search engines. Search engines use vector embeddings extensively to improve the effectiveness and efficiency of information retrieval. Since vector embeddings go beyond keyword matching, they help search engines interpret the meaning of words and sentences. Even when the exact phrases don't match, search engines can still find and retrieve documents or other information that's contextually relevant by modeling words as vectors in a semantic space.
  • Chatbots and question-answering-systems. Vector embeddings aid chatbots and generative AI-based question-answering systems in the understanding and production of human-like responses. By capturing the context and meaning of text, embeddings help chatbots respond to user inquiries in a meaningful and logical manner. For example, language models and AI chatbots, including GPT-4 and image processors such as Dall-E2, have gained immense popularity for producing human-like conversations and responses.
  • Fraud detection and outlier detection. Vector embeddings can be used to detect anomalies or fraudulent activities by assessing the similarity between vectors. Uncommon patterns are identified by evaluating the distance between embeddings and pinpointing outliers.
  • Data preprocessing. To transform unprocessed data into a format that's appropriate for ML and deep learning models, embeddings are used in data preprocessing activities. Word embeddings, for instance, are used to represent words as vectors, which facilitates the processing and analysis of text data.
  • One-shot and zero-shot learning. One-shot and zero-shot learning are vector embedding approaches that help machine learning models predict outcomes for new classes, even when supplied with limited labeled data. Models can generalize and generate predictions even with a small number of training instances by using the semantic information included in embeddings.
  • Semantic similarity and clustering. Vector embeddings make it easier to gauge how similar two objects are in a high-dimensional environment. This makes it possible to do operations such as computing semantic similarity, clustering and assembling of related things based on their embeddings.
Image showing vector embedding in chatbots.
Embeddings let chatbots respond to user inquiries in a meaningful and logical way.

What type of things can be embedded?

Many different kinds of objects and data types can be represented using vector embeddings. Common types of things that can be embedded include the following:


Words, phrases or documents are represented as vectors using text embeddings. NLP tasks -- including sentiment analysis, semantic search and language translation -- frequently use embeddings.

The Universal Sentence Encoder is one of the most popular open source embedding models and it can efficiently encode individual sentences and whole text chunks.


Image embeddings capture and represent visual characteristics of images as vectors. Their use cases include object identification, picture classification and reverse image search, often known as search by image.

Image embeddings can also be used to enable visual search capabilities. By extracting embeddings from database images, a user can compare the embeddings of a query image with the embeddings of the database photos to locate visually similar matches. This is commonly used in e-commerce apps, where users can search for items by uploading photos of similar products.

Google Lens is an image-searching application that compares camera photos to visually similar products. For example, it can be used to match internet products that are similar to a pair of sneakers or a piece of clothing.


Audio embeddings are vector representations of audio signals. Vector embeddings capture auditory properties, letting systems interpret audio data more effectively. For example, audio embeddings can be used for music recommendations, genre classifications, audio similarity searches, speech recognition and speaker verification.

While AI is being used for various types of embeddings, audio AI has received less attention than text or image AI. Google Speech-to-Text and OpenAI Whisper are audio embedding applications used in organizations such as call centers, medical technology, accessibility and speech-to-text applications.


Graph embeddings use vectors to represent nodes and edges in a graph. They're used in tasks related to graph analytics such as link prediction, community recognition and recommendation systems.

Each node represents an entity, such as a person, a web page or a product and each edge symbolizes the link or connection that exists between those entities. These vector embeddings can accomplish everything from recommending friends in social networks to detecting cybersecurity issues.

Time series data and 3D models

Time series embeddings capture temporal patterns in sequential data. They're used in internet of things applications, financial data and sensor data for activities including anomaly detection, time series forecasting and pattern identification.

Geometric aspects of 3D objects can also be expressed as vectors using 3D model embeddings. They're applied in tasks such as 3D reconstruction, object detection and form matching.


Molecule embeddings represent chemical compounds as vectors. They're used in drug discovery, chemical similarity searching and molecular property prediction. These embeddings are also used in computational chemistry and drug development to capture the structural and chemical features of molecules.

Image showing vector embeddings of objects.
Structured sets of numbers are used as vector embeddings for objects.

What is Word2Vec?

Word2Vec is a popular NLP word vector embedding approach. Created by Google, Word2Vec is designed to represent words as dense vectors in a continuous vector space. It can recognize the context of a word in a document and is commonly used in NLP tasks such as text categorization, sentiment analysis and machine translation to help machines comprehend and process natural language more effectively.

Word2Vec is based on the principle that words with similar meanings should have similar vector representations, enabling the model to capture semantic links between words.

Word2Vec has two basic architectures, CBOW (Continuous Bag of Words) and Skip-Gram:

  • CBOW. This architecture predicts the target word based on the context words. The model is given a context or surrounding words and is tasked with predicting the target word in the center. For example, in the sentence, "The quick brown fox jumps over the lazy dog," CBOW uses the context or surrounding words to predict fox as the target word.
  • Skip-Gram. Unlike CBOW, the Skip-Gram architecture predicts the context words based on the target word. The model is given a target word and is asked to predict the surrounding context terms. Taking the above example sentence of "The quick brown fox jumps over the lazy dog," skip-gram will take the target word fox and discover context words such as "The," "quick," "brown," "jumps," "over," "the," "lazy" and "dog."

A wide range of businesses are beginning to embrace generative AI, demonstrating its disruptive potential. Examine how generative AI is developing, what direction it will go in the future and any challenges that might arise.

This was last updated in May 2024

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