The User Integer node texture allows the user to read and return a single integer value from the currently shaded object as a result. This can be useful if the same material or texture is applied to several objects in the scene, but you want to control some of its properties with user-defined properties. Visit the User Attributes Workflow page for information and tutorials on user-defined properties. 

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User Attribute – Specifies the name of the user attribute that is looked up and returned from this utility texture.

Default value – Specifies the value to return if the user attribute is not found on the shaded object.