The Bing Image Search API returns a list of relevant images from a search query which include thumbnails, full image URLs, publishing website information, and image metadata. Also, it offers several filters such as image type, layout, freshness, and license. This API provides a list of images similar to the "Bing.com/Images" site. The Image Search API uses JSON format for data exchange, and API Keys for authentication. Free trial keys are available here: https://azure.microsoft.com/en-us/try/cognitive-services/?api=bing-image-search-api.