arangodb/Documentation/Books/Users/Collections

!CHAPTER JavaScript Interface to Collections

This is an introduction to ArangoDB's interface for collections and how to handle
collections from the JavaScript shell _arangosh_. For other languages see the
corresponding language API.

The most important call is the call to create a new collection.

!SECTION Address of a Collection 

All collections in ArangoDB have a unique identifier and a unique
name. ArangoDB internally uses the collection's unique identifier to look up
collections. This identifier, however, is managed by ArangoDB and the user has
no control over it. In order to allow users to use their own names, each collection
also has a unique name which is specified by the user. To access a collection
from the user perspective, the [collection name](../Glossary/index.html#collection_name) should be used, i.e.:

!SUBSECTION Collection
`db._collection(collection-name)`

A collection is created by a ["db._create"](../Collections/DatabaseMethods.md) call.

For example: Assume that the [collection identifier](../Glossary/index.html#collection_identifier) is *7254820* and the name is
*demo*, then the collection can be accessed as:

    db._collection("demo")

If no collection with such a name exists, then *null* is returned.

There is a short-cut that can be used for non-system collections:

!SUBSECTION Collection name
`db.collection-name`

This call will either return the collection named *db.collection-name* or create
a new one with that name and a set of default properties.

**Note**: Creating a collection on the fly using *db.collection-name* is
not recommend and does not work in _arangosh_. To create a new collection, please
use

!SUBSECTION Create
`db._create(collection-name)`

This call will create a new collection called *collection-name*.
This method is a database method and is documented in detail at [Database Methods](../Collections/DatabaseMethods.html#create)