Possible types for targeting.

TARGETING_TYPE_UNSPECIFIED Default value when type is not specified or is unknown in this version.
TARGETING_TYPE_CHANNEL Target a channel (a custom group of related websites or apps).
TARGETING_TYPE_APP_CATEGORY Target an app category (for example, education or puzzle games).
TARGETING_TYPE_APP Target a specific app (for example, Angry Birds).
TARGETING_TYPE_URL Target a specific url (for example,
TARGETING_TYPE_DAY_AND_TIME Target ads during a chosen time period on a specific day.
TARGETING_TYPE_AGE_RANGE Target ads to a specific age range (for example, 18-24).
TARGETING_TYPE_REGIONAL_LOCATION_LIST Target ads to the specified regions on a regional location list.
TARGETING_TYPE_PROXIMITY_LOCATION_LIST Target ads to the specified points of interest on a proximity location list.
TARGETING_TYPE_GENDER Target ads to a specific gender (for example, female or male).
TARGETING_TYPE_VIDEO_PLAYER_SIZE Target a specific video player size for video ads.
TARGETING_TYPE_USER_REWARDED_CONTENT Target user rewarded content for video ads.
TARGETING_TYPE_PARENTAL_STATUS Target ads to a specific parental status (for example, parent or not a parent).
TARGETING_TYPE_CONTENT_INSTREAM_POSITION Target video or audio ads in a specific content instream position (for example, pre-roll, mid-roll, or post-roll).
TARGETING_TYPE_CONTENT_OUTSTREAM_POSITION Target ads in a specific content outstream position.
TARGETING_TYPE_DEVICE_TYPE Target ads to a specific device type (for example, tablet or connected TV).
TARGETING_TYPE_AUDIENCE_GROUP Target ads to an audience or groups of audiences. Singleton field, at most one can exist on a single Lineitem at a time.
TARGETING_TYPE_BROWSER Target ads to specific web browsers (for example, Chrome).
TARGETING_TYPE_HOUSEHOLD_INCOME Target ads to a specific household income range (for example, top 10%).
TARGETING_TYPE_ON_SCREEN_POSITION Target ads in a specific on screen position.
TARGETING_TYPE_THIRD_PARTY_VERIFIER Filter web sites through third party verification (for example, IAS or DoubleVerify).
TARGETING_TYPE_DIGITAL_CONTENT_LABEL_EXCLUSION Filter web sites by specific digital content label ratings (for example, DL-MA: suitable only for mature audiences).
TARGETING_TYPE_SENSITIVE_CATEGORY_EXCLUSION Filter website content by sensitive categories (for example, adult).
TARGETING_TYPE_ENVIRONMENT Target ads to a specific environment (for example, web or app).
TARGETING_TYPE_CARRIER_AND_ISP Target ads to a specific network carrier or internet service provider (ISP) (for example, Comcast or Orange).
TARGETING_TYPE_OPERATING_SYSTEM Target ads to a specific operating system (for example, macOS).
TARGETING_TYPE_DEVICE_MAKE_MODEL Target ads to a specific device make or model (for example, Roku or Samsung).
TARGETING_TYPE_KEYWORD Target ads to a specific keyword (for example, dog or retriever).
TARGETING_TYPE_NEGATIVE_KEYWORD_LIST Target ads to a specific negative keyword list.
TARGETING_TYPE_VIEWABILITY Target ads to a specific viewability (for example, 80% viewable).
TARGETING_TYPE_CATEGORY Target ads to a specific content category (for example, arts & entertainment).
TARGETING_TYPE_INVENTORY_SOURCE Purchase impressions from specific deals and auction packages.
TARGETING_TYPE_LANGUAGE Target ads to a specific language (for example, English or Japanese).
TARGETING_TYPE_AUTHORIZED_SELLER_STATUS Target ads to ads.txt authorized sellers.
TARGETING_TYPE_GEO_REGION Target ads to a specific regional location (for example, a city or state).
TARGETING_TYPE_INVENTORY_SOURCE_GROUP Purchase impressions from a group of deals and auction packages.
TARGETING_TYPE_EXCHANGE Purchase impressions from specific exchanges.
TARGETING_TYPE_SUB_EXCHANGE Purchase impressions from specific sub-exchanges.