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What is a vector database?
A vector database is a place that stores text, images or sound as numbers so a computer can find things with similar meaning.
- Category Agents & tools
- Also called vector DB, vector store
- Updated 20 Oct 2026
Vector database, explained simply
A vector database stores data as long lists of numbers. These numbers capture what something means. Items with similar meaning end up close together.
It matters because it lets search work on ideas, not only exact words. You can look for "cheap flights" and also find "low-cost airfare".
For example, an AI tool can store your notes in a vector database. When you ask a question, it pulls the notes closest in meaning.
They are a common part of RAG tools.
On ITG Now, our free tool guides name the vector database a project uses and say whether it installs with the tool.
Related terms
EmbeddingsRAGSemantic searchAI memory
Questions people ask about Vector database
Is a vector database free?
Many are open source and free to run yourself. Hosted versions usually charge.
Vector database vs regular database: what is the difference?
A regular one finds exact matches. A vector database finds items that are close in meaning.
Do I need a vector database to use AI?
No. You only need one if you build tools that search large piles of text by meaning.