We can consider a resource to be one of many members of a very broad category, as the unique instance of a category with only one member, or anywhere in between.

(See §3.1.1, “What Is a Resource?”)

The size of the category—the number of resources that are treated as equivalent—is determined by the properties or characteristics we consider when we examine the resource.

(See §3.1.1, “What Is a Resource?”)

Organizing systems for physical information resources emphasize description resources or surrogates like bibliographic records that describe the information content rather than their physical properties.

(See §3.1.1.2, “Bibliographic Resources, Information Components, and “Smart Things” as Resources”)

An identifier is a special kind of name assigned in a controlled manner and governed by rules that define possible values and naming conventions. The design of a scheme for persistent identifiers must consider both the required time frame and the number of resources to be identified.

(See §3.1.2, “Identity, Identifiers, and Names”)

Active resources create effects or value on their own, sometimes when they initiate interactions with passive resources. Active resources can be people, other living resources, computational agents, active information sources, web-based services, self-driving cars, robots, appliances, machines or otherwise ordinary objects like light bulbs, umbrellas, and shoes that have been made “smarter.”

(See §3.2.3.2, “Active or Operant Resources”)

More fine-grained organization reduces recall, the number of resources you find or retrieve in response to a query, but increases the precision of the recalled set, the proportion of recalled items that are relevant.

(See §3.3.3, “Identity and Information Components”)

Agency is the extent to which a resource can initiate actions on its own. We can define a continuum between completely passive resources that cannot initiate any actions and active resources that can initiate actions based on information they sense from their environments or obtain through interactions with other resources.

(See §3.2.3, “Resource Agency”)

Resources become active resources when they contain sensing and communication capabilities.

(See §3.2.3, “Resource Agency”)

Organizing systems that create value from active resources often co-exist with or complement organizing systems that treat its resources as passive.

(See §3.2.3, “Resource Agency”)

Which resources are primary and which are metadata is often just a decision about which resource is the focus of our attention.

(See §3.2.4, “Resource Focus”)

It can be useful to view domains of information resources on the Document Type Spectrum from weakly-structured narrative content to highly structured transactional content.

(See the sidebar, The Document Type Spectrum)

The concept of identity for bibliographic resources has evolved into a four-level abstraction hierarchy between the abstract work, an expression in multiple formats or genres, a particular manifestation in one of those formats or genres, and a specific physical item.

(See §3.3.2, “Identity and Bibliographic Resources” and Figure 3.5, “The FRBR Abstraction Hierarchy for Identifying Resources.”)

If the resource has an IP address, it is said to be part of the “Internet of Things.”

(See §3.3.4, “Identity and Active Resources”, including 157[Com] and 158[Com].)

Every natural language offers more than one way to express any thought, and in particular there are usually many words that can be used to refer to the same thing or concept. The words people choose to name or describe things are embodied in their experiences and context, so people will often disagree in the words they use. Moreover, people are often a bit surprised when it happens, because what seems like the natural or obvious name to one person is not natural or obvious to another.

(See §3.4.2, “The Problems of Naming”)

Many resources are given names based on attributes that can be problematic later if the attribute changes in value or interpretation.

(See §3.4.2.4, “Names that Assume Impermanent Attributes”)

The semantic gap is the difference in perspective in naming and description when resources are described by automated processes rather than by people.

(See §3.4.2.5, “The Semantic Gap”)

The most basic principle of naming is to choose names that are informative.

(See §3.4.3.1, “Make Names Informative”)

One way to encourage good names for a given resource domain or task is to establish a controlled vocabulary. A controlled vocabulary can be thought of as a fixed or closed dictionary that includes all the terms that can be used in a particular domain. A controlled vocabulary shrinks the number of words used, reducing synonymy and homonymy and eliminating undesirable associations, leaving behind a set of words with precisely defined meanings and rules governing their use.

(See §3.4.3.2, “Use Controlled Vocabularies”)

For bibliographic resources important aspects of vocabulary control include determining the authoritative forms for author names, uniform titles of works, and the set of terms by which a particular subject will be known. In library science, the process of creating and maintaining these standard names and terms is known as authority control.

(See §3.4.3.2, “Use Controlled Vocabularies”)

Preservation and governance are activities carried out to ensure the outcome of persistence.

(See §3.5.1, “Persistence”)

Many resources, or their properties, also have locative or temporal effectivity, meaning that they come into effect at a particular time and/or place; will almost certainly cease to be effective at some future date, and may cease to be effective in different places.

(See §3.5.2, “Effectivity”)