Enum describing the various advertising channel types.

UNSPECIFIED Not specified.
UNKNOWN Used for return value only. Represents value unknown in this version.
SEARCH Search Network. Includes display bundled, and Search+ campaigns.
DISPLAY Google Display Network only.
SHOPPING Shopping campaigns serve on the shopping property and on search results.
HOTEL Hotel Ads campaigns.
VIDEO Video campaigns.
MULTI_CHANNEL App Campaigns, and App Campaigns for Engagement, that run across multiple channels.
LOCAL Local ads campaigns.
SMART Smart campaigns.
PERFORMANCE_MAX Performance Max campaigns.
LOCAL_SERVICES Local services campaigns.
DISCOVERY Discovery campaigns.
TRAVEL Travel campaigns.