RE:I Write Micro Fiction
From what I've read online, they're the same.
From my perspective though, there's a difference. It's the word count which I put at 100 words. It can be less but not more than 200 maybe. Beyond that, it's flash fiction.
I make this distinction to maintain my focus and motivate myself to write. If I think of the 200+ word count, I'll run out of words, tell myself I can't do this anymore.
I'm new to writing fiction seriously as a vocation. I want to start it short, maybe just keep it at that and be an expert and a best-selling micro fictionist.
Hope I answered your question...