---
title: Dictionaries
summary: null
url: https://www.fastly.com/documentation/reference/api/dictionaries
---

A [dictionary](https://www.fastly.com/documentation/guides/concepts/edge-state/dynamic-config/#edge-dictionaries) is a key-value data store accessible to VCL during request processing.

Dictionaries have two primary parts: the dictionary container and the items within it. Once you attach a dictionary container to a version of your service and that service is activated, the data in the container (the dictionary items) becomes "versionless." This means that any updates to the items will take effect immediately, without requiring a new version of the service. We also expose a separate dictionary info resource to report up-to-date metadata about your dictionary.

To find out more about using dictionaries in your service, see our [guide to dynamic configuration](https://www.fastly.com/documentation/guides/concepts/edge-state/dynamic-config/#edge-dictionaries).

- [Dictionary](https://www.fastly.com/documentation/reference/api/dictionaries/dictionary/) - A Dictionary is a VCL data table that stores key-value pairs accessible to VCL during request processing. New, empty dictionaries can be attached to a draft version of a service, which must be activated for the dictionary to be included in VCL. Once installed, a dictionary's items may be updated via API calls without having to activate a new version of the associated service configuration. To remove a dictionary, delete it on a draft version of a service (one that is not locked and not active). Once removed, activate the draft service version without the dictionary.
- [Dictionary info](https://www.fastly.com/documentation/reference/api/dictionaries/dictionary-info/) - Dictionary Info is a set of metadata describing properties of a dictionary which change as items are added and removed.
- [Dictionary item](https://www.fastly.com/documentation/reference/api/dictionaries/dictionary-item/) - A Dictionary Item is a single key-value pair that makes up an entry in a Dictionary. Dictionary Items can be added, removed and modified without activating a new version of the associated service.