An explanation of how I use them.
Reading romance can be tricky if you are seeking a specific steam/heat level.
But first, what do we mean when we talk about heat/steam? Well, there's no standard shared definition, but generally it means how sexy and explicit a book is. Older descriptions used a binary: open or closed door (did you see the action, or not?). Now a lot of authors and reviewers are trying to be as clear as possible so readers can find the right story for them.
I use "candles" to denote hot steamy a story is, and I break it down below so you know what to expect. Most of my stories live in either a 3 or 4 candle rating.
Note: these levels do not mean anything about a character's sexuality.
What you see: very light kissing, if any. These stories are focused entirely on the mental aspect of romance without any description of the physical.
What you see: kissing (without detailed description), flirting, sexual tension, maybe grinding, over the clothes touching (again without detailed description), allusions to sex scenes
What you don't see: the sex scenes, descriptions of nudity
What you see: everything from the above, with more detail, plus more foreplay, perhaps some descriptions of nudity. Usually 1 sex scene per book.
What you might see: everything from the above, with explicit detail, explicit descriptions of nudity, dirty talk, sexting, sexual teasing, pet names/nicknames, light roleplaying, light kink exploration, butt stuff. Usually 2-3 sex scenes per book.
What you might see: everything from the above, plus: possibly BDSM, heavier kink exploration, sex as more central to the plot. Usually 3-5 sex scenes per book.
What you might see: Everything! Sex is critical to the plot of these books and they are classified as erotica, instead of erotic romance (meaning the point of the plot, if there is one, is for sexy times, not romance).