Terminology
A Meta Field consists of a Meta Key, which defines the property you're defining, and a Meta Value, which is the value of the property. For example, the Meta Key "gs1_template" may have a Meta Value of "Default".
Why would I use them?
You could use Meta Values to store arbitrary data Whiplash doesn't need to ship Orders, but you need on the Packing Slip or some other resource. They can also be used in Search Filters, which can be applied to Rules, Bulk Actions, or reporting.
Access
We don't accept arbitrary Meta Keys. They must first be validated and created by an Admin. Right now, Admins can access Manage → Meta Keys to create and adjust them.

Adding Meta Values to Orders
How can I use them in Templates?
How can I use them in Search and Rules?
There's a Search Filter for Meta Fields which accepts a Key: Value pair like "embroidery: 1" or "oms-reference: ABC123". Regex is not currently accepted, only exact searches.
Notes:
Notes:
- For best results, combine the Meta Fields with another search filter like Status.
- True / False values accept 1 and 0, respectively.