Arghhh sorry I lost track of my comments over the crazy holidays! Such an interesting question. I guess in terms of purpose, the biggest difference I've noticed is that most asides tend to help the audience understand things a bit more, but the character is rarely discovering anything new. It's almost always, "Yes, yes, that thing is happening, just as I suspected, and I'm going to do this next, just as I planned... my plan is working!" Whereas in a soliloquy, the character pretty much always discovers or decides something new. Consequently they FEEL very different to an actor and to the audience. Asides usually have a lot of energy and keep things moving, but soliloquys feel more like, "I'm going to stop everything now and talk until I figure this out!" Even if it's an energetic soliloquy, it still requires the character to put the brakes on for a minute before they move on. These are generalisations of course, but that's how I would sum up the difference as a general rule.

​@@ShakespearewithSarah Thank you for your insight, I never thought about it in that way before.