What do we mean with external ID, entity ID or different IDs?

External ID

This is the main ID used to identify a e.g. campaign, flight,... you created. Typically here you use your own primary ID from your system or generate one and store it.

Entity IDs

When creating e.g. a campaign you can supply entity IDs. With Entity ID we actually mean the goTom internal ID you can find sometimes in the frontend in the URL e.g. /customer/123 where 123 would be the goTom internal ID. Another example would be when creating a flight, tarifId is as well a goTom internal ID. You can read out those IDs using the endpoint Primary Keys.