Margin

Margin is the difference between Price and Cost. Margin can be expressed in three ways in Prism: Margin %, Markup, and Coefficient.

A change made to price, cost, or margin always causes a change to one of the other values. If you edit cost or price, the Margin %, MarkUp %, and Coefficient will change.  If you edit the Margin %, MarkUp %, or Coefficient, the Price or Cost will change.
You can view an item's Margin Percent and Amount by viewing the item's record and navigating to the Price/Cost tab.
Sample item record (Price/Cost tab) showing Margin fields:

Editing Margin
In Prism Node Preferences > Merchandise > Inventory > General, you can choose whether changes to margin affect price or cost. Note: When using sales tax, you typically want changes in margin to affect an item's cost; when using VAT, you typically want changes in margin to affect an item's price.

Sample Margin Values