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Data standards include both an identification of relevant entries as well as definition of entries and where reasonable, inclusion of units associated with entries.
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Metadata standards are similar in that they identify relevant entries, describe entries, and include units but are focused on properties that are data-agnostic (e.g., well info where both quantity and quality measurements can be captured)
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Crosswalk
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This page contains a brief description of common words that we use in our TWG conversations 
. FYI, IT-specific terms are available here: Glossary of Terms
Crosswalks: Conduct a map of how information within original data sources align with the data and metadata standards (e.g., see example crosswalk for Wells)
Dictionary: a text-based description of column names within a given dataset. Additional details, such as the units used and format of information (character vs. integer) are often included within the dictionary.
SensorThings (ST): ST is a data model to develop a common “language” around the different types of water data. ST is a service focused on data streaming that supports integration of metadata within the data structure. Descriptions for the entries within ST are available here.
Standards: Summary of units and data fields that facilitate aggregation of data throughout the WDI so that we have a common format (and minimal set of details) to use when information is being reported/displayed.
Data standards describe the kinds of information we want to include for a given dataset/data type. For example, for groundwater levels, this would capture information about date, depth below to ground surface, etc.
Metadata standards describe the format in which data is collected or recorded (e.g., YYYY-MM-DD for dates and “feet” for depth below ground surface).
Both data and metadata-related content are captured within the SensorThings framework under the associated elements.
Units within original data sources can be of any format but should be well-described to facilitate integration.