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In an ideal world, metadata would always be prepared in a machine-readable format. Some tools (metadata editors) exist to assist with that process, but they may be associated with a particular metadata standard or type of data. If that is not an option, you can still document your data in simple metadata forms.
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Our recommendation for spatial data is to populate the metadata component of your geospatial file. ArcCatalog allows you to enter metadata for each layer in Federal Geographic Data Committee (FGDC) or ISO (recommended) format.
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