+SPDX-License-Identifier: CC-BY-SA-3.0
+{% endcomment %}
+
+API endpoint base: @https://{{ site.arvados_api_host }}/arvados/v1/collections@
+
+Object type: @4zz18@
+
+Example UUID: @zzzzz-4zz18-0123456789abcde@
+
+h2. Resource
+
+Collections describe sets of files in terms of data blocks stored in Keep. See "Keep - Content-Addressable Storage":{{site.baseurl}}/architecture/storage.html and "using collection versioning":../../user/topics/collection-versioning.html for details.
+
+Each collection has, in addition to the "Common resource fields":{{site.baseurl}}/api/resources.html:
+
+table(table table-bordered table-condensed).
+|_. Attribute|_. Type|_. Description|_. Example|
+|name|string|||
+|description|text|||
+|properties|hash|User-defined metadata, may be used in queries using "subproperty filters":{{site.baseurl}}/api/methods.html#subpropertyfilters ||
+|portable_data_hash|string|The MD5 sum of the manifest text stripped of block hints other than the size hint.||
+|manifest_text|text|||
+|replication_desired|number|Minimum storage replication level desired for each data block referenced by this collection. A value of @null@ signifies that the site default replication level (typically 2) is desired.|@2@|
+|replication_confirmed|number|Replication level most recently confirmed by the storage system. This field is null when a collection is first created, and is reset to null when the manifest_text changes in a way that introduces a new data block. An integer value indicates the replication level of the _least replicated_ data block in the collection.|@2@, null|
+|replication_confirmed_at|datetime|When @replication_confirmed@ was confirmed. If @replication_confirmed@ is null, this field is also null.||
+|storage_classes_desired|list|An optional list of storage class names where the blocks should be saved. If not provided, the cluster's default storage class(es) will be set.|@['archival']@|
+|storage_classes_confirmed|list|Storage classes most recently confirmed by the storage system. This field is an empty list when a collection is first created.|@'archival']@, @[]@|
+|storage_classes_confirmed_at|datetime|When @storage_classes_confirmed@ was confirmed. If @storage_classes_confirmed@ is @[]@, this field is null.||
+|trash_at|datetime|If @trash_at@ is non-null and in the past, this collection will be hidden from API calls. May be untrashed.||
+|delete_at|datetime|If @delete_at@ is non-null and in the past, the collection may be permanently deleted.||
+|is_trashed|boolean|True if @trash_at@ is in the past, false if not.||
+|current_version_uuid|string|UUID of the collection's current version. On new collections, it'll be equal to the @uuid@ attribute.||
+|version|number|Version number, starting at 1 on new collections. This attribute is read-only.||
+|preserve_version|boolean|When set to true on a current version, it will be persisted. When passing @true@ as part of a bigger update call, both current and newly created versions are persisted.||
+|file_count|number|The total number of files in the collection. This attribute is read-only.||
+|file_size_total|number|The sum of the file sizes in the collection. This attribute is read-only.||
+
+h3. Conditions of creating a Collection
+
+If a new @portable_data_hash@ is specified when creating or updating a Collection, it must match the cryptographic digest of the supplied @manifest_text@.
+
+h3. Side effects of creating a Collection
+
+Referenced blocks are protected from garbage collection in Keep.
+
+Data can be shared with other users via the Arvados permission model.
+
+h2. Methods
+
+See "Common resource methods":{{site.baseurl}}/api/methods.html for more information about @create@, @delete@, @get@, @list@, and @update@.