This is a proposal from Google based on our experience consuming schema.org Product markup and working with similar data from online merchants. If it were accepted, it would allow merchants to add product highlights to their product structured data, and allow us and others to better understand products sold online.

Description

Products advertised or sold online are often displayed not only with a title and description, but also with more detailed information, such as a list of product highlights, which are easy to consume and quick to scan ordered bullet points emphasizing the relevant attributes of a product. For example:

• Capture quality 24mp photos and UHD video in an easy to use point and shoot camera with a 2.8" preview screen
• Excellent for underwater photography, submersible up to 16 feet
• Protective plastic cover to protect from scratches
• A great first DSLR camera with enough features for novice photographers of any age
• Uses 2 AAA Batteries (included) and saves videos to a mini SD card (not included)

To support ordered highlight lists we propose to introduce a new property /highlights of type /ItemList (for use on /Product). The example given above could then be represented as follows:

{
  "@context": "https://schema.org/",
  "@type": "Product",
  "sku": "camera-12345",
  "image": "https://www.example.com/camera.jpg",
  "name": "Nice camera",
  "description": "Compact DSLR camera with pancake lens",
  "gtin": "12345678901234",
  "brand": {
    "@type": "Brand",
    "name": "CameraBrand"
  },
  "color": "black",
  "offers": {
    "@type": "Offer",
    "url": "http://www.example.com/camera_offer",
    "itemCondition": "https://schema.org/NewCondition",
    "availability": "https://schema.org/Backorder",
    "price": "539.99",
    "priceCurrency": "EUR"
  },
  "highlights": {
    "@type": "ItemList",
    "itemListElement": [
      {
        "@type": "ListItem",
        "position": 1,
        "item": "Capture quality 24mp photos and UHD video in an easy to use point and shoot camera with a 2.8\" preview screen"
      },
      {
        "@type": "ListItem",
        "position": 2,
        "item": "Excellent for underwater photography, submersible up to 16 feet"
      },
      {
        "@type": "ListItem",
        "position": 3,
        "item": "Protective plastic cover to protect from scratches"
      },
      {
        "@type": "ListItem",
        "position": 4,
        "item": "A great first DSLR camera with enough features for novice photographers of any age"
      },
      {
        "@type": "ListItem",
        "position": 5,
        "item": "Uses 2 AAA Batteries (included) and saves videos to a mini SD card (not included)"
      }
    ]
  }
}

It is important to note that the present proposal suffers from the same disadvantage as for example #2832, i.e., it requires verbose markup to support explicit ordering of list elements. Eventually (but outside scope of this proposal) it would be beneficial to support ordered elements with syntactic sugar or even an extension of RDFS since ordered elements are a very common need and would benefit from a more concise notation.