Is Sprint 0 a scrum event?

There is NO! Sprint 0 in SCRUM.

What do you mean by a "Sprint 0" in this case? You can number or name a sprint any way you like.

So what are the characteristics of the "Sprint 0" you are thinking of, which would distinguish it from other Sprints? From your reading of the Scrum Guide, what are the essential characteristics of a Sprint?

Absolutely not!

The purpose of any Sprint is to deliver value. The guide helps you focus on this.

Scrum values research as a part of development.  As you research and your timelines change, you react.  Sometimes that means breaking up your stories, sometimes it means contacting your Scrum Master to remove an impediment, and sometimes you get lucky and everything goes way faster than expected.  In each case, you react and adapt to new information, rather than gathering information and formulating a detailed plan.



Remember, Scrum is all about delivering increments of value.  You can't deliver research, so you want to avoid making research be a standalone item.  All the practices of "Sprint 0" or "Research Sprints" should naturally be occurring alongside your normal sprints.



Trying to do all your research and backlog breakdowns first, then progressing to development afterwards isn't Scrum.  It's Waterfall with a timebox.

I would say Why Not?

Does Scrum Guide mention anything about naming a Sprint, you can name it anything - Oscar, Apple, Dell etc However it should comply with the definition of Sprint written in the Scrum guide.

There is no such thing as a Sprint 0.