Using ArcCatalog

Writing documentation
Automatically generated metadata is not a substitute for good
documentation—it just helps to reduce metadata maintenance
costs. Good documentation protects your investment in the
resources you have created or purchased. For example, without
knowledge of data accuracy, provenance, and age, you can’t
have a high level of confidence in decisions based on that data.
Documenting your GIS resources also provides you with information
that can be used to build or contribute to a GIS catalog portal
such as an ArcIMS Metadata Service. Whether internal to your
organization or available on the Internet, portals let others search,
find, and access the GIS resources they need.
Metadata standards
Following a well-known metadata standard is a good idea
because tools will already exist with which you can create
metadata. For those who plan to publish their metadata to a wide
audience, following a standard also makes it easier for people
from different communities, industries, and countries to understand
each others’ documentation because the standard acts as a
dictionary, defining terminology and the expected values.
There are a number of metadata content standards to choose
from. The FGDC standard aims to provide a complete description
of a data source. Because it’s quite detailed, other states and
regions have created their own metadata standards to try to
simplify the information that should be recorded. For example, the
European Committee for Standardization (CEN) and the Australia
New Zealand Land Information Council (ANZLIC) have created
their own metadata standards and guidelines.
Also, this year the ISO standard will be finalized. Designed with
an international audience in mind, it attempts to provide a
solution that will satisfy the requirements of all existing standards.
It allows for either general or detailed descriptions of data
sources, makes some allowances for describing resources other
than data, and has a small number of mandatory elements.
Simply because so many standards exist, metadata in ArcCatalog
isn’t required to meet any specific standard. However, your
organization may be required to follow a particular standard. For
example, U.S. federal government departments must provide
metadata following the FGDC standard. But, in time, the FGDC
and most other standards organizations are committed to
adopting the ISO standard. This move should help eliminate some
of the barriers to sharing data worldwide.
If you’ve chosen to follow a specific metadata standard, a few
pieces of information will be considered mandatory in order for
your metadata to be considered compliant with that standard.
Keep in mind that blindly following a standard’s rules is not the
way to create good metadata. This is particularly true for organizations
that decide to add only the required pieces of documentation.
A good book is not written in a day. Good documentation for
a GIS resource will not be written in two minutes.
Generally people choose to create minimal metadata in order to
cross the task off their list and to reduce its costs. However, in
doing so they sacrifice the usefulness of that documentation.
What documentation to provide
As with any project you should have a plan outlining what
content your metadata should include. Look over the metadata
standard you’ve chosen to follow to get an idea of the content it
suggests. However, you ultimately need to decide what pieces of
documentation are most important to your organization based on
how you intend to use it.
If you plan to publish your metadata so that people can find your
resources by doing a search, you need to consider what information
needs to be present to do different types of searches.
Typically, people will search by keywords describing the theme or
subject of the resource; by the type of resource; by how current
it is; and, depending on the portal, by the publisher of the
resource. Keywords are more useful if they are derived from a
thesaurus; otherwise, you might be searching for roads while the
data you’re looking for is described as streets.
132 USING ARCCATALOG