Links are similar to hyperlinks, which can reference external assets. You can add links to a feature class or to individual features. You can link features to an URL, an image, tooltips or a map.
If you specify a link for an entire feature class, all features in that class will use the same link definition. If you specify a different link for one feature in that feature class, that feature's link will override the feature class link setting.
If you link a feature to a map (for example, using the link string from Google Maps), you must substitute the feature's latitude/longitude properties for the ones in the string. Otherwise, the differences in the co-ordinate systems will result in an inaccurate location.
Link is near the bottom of the Common section.
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