I'm having trouble researching a particular design pattern because I don't know what to call it -- internally we refer to this concept as a "hot spot" but that doesn't seem to be standard jargon. It involves clicking an icon within an image, which launches an overlay with more details.
For example: you may have a photo of a kitchen with "+" symbol icons next to some features, such as the sink, dishwasher, microwave, etc. Clicking the "+" symbol would show an overlay with a larger view of that item and potentially an accompanying text description. It's more information than a tooltip, but not as extreme as a modal layer (because the user can still interact with other items on the screen, such as clicking another "+" icon).
My question is whether there is any data/research on whether this is an effective design pattern to explore features (and if so, does it have a common name)? My gut is this is a relic from the "everything must be above the fold" days of design, and is an inefficient way to show information, as it requires constant clicking to explore items and only allows you to see one feature at a time (my preference would be to either show all the information on a longer page or use a gallery-like interface), but I'm on a team where this is very strongly being pushed as a more "interactive/immersive" experience and I need something more than gut feeling to use as a response.