Before you add key-values, you should understand the difference between a name and a display name. Both need to be entered when creating a key-value.
The "Name" is text that's used in ad tags. The name you enter may appear in an ad request URL, which can potentially be seen by people who visit your website or app if they inspect the ad request. The "Display name" is what traffickers see in the targeting picker when adding custom targeting line items, proposal line items, or other items in Ad Manager.
Most publishers believe it's good practice to use shorter names for key-values. Shorter names improve performance of ad serving as there are fewer bytes to process for an ad request—and there could be certain character limits in the ad request. There are also certain limits for key-values targeting in the targeting picker itself.
A Name for a key might be entered something like this for example:
This text would be used in ad tags and passed in ad requests. A Name could represent a Display name, such as:
The "age" display name is what traffickers see in the targeting picker. The same principle applies when you add values. You must first enter the name of value before you can enter its display name. So, for the key in our example, you might enter:
Once you've saved them to the key, you can define their display names. In this example, you might enter the following display names for each of the names shown above respectively:
Display names can make it easier to understand what's being targeted. In ad request, however, visitors to your webpage only see the name you defined if the ad request URL is inspected. They might only see, in our example, the following:
In reports, you see both the name and display name.