What Is: The Increment
Over the years, the Increment has had several different names, and different definitions. Some of those names and abbreviations are: Potentially Shippable Product Increment (PSPI), Potentially Shippable Increment (PSI), Product Increment (PI). Per the most recent version of the Scrum Guide, we now just call it the Increment.
What is it?
The Increment is, simply put, the accumulation of all completed work from previous Sprints, and the current Sprint. Think of it as an ever-growing snowball. The current Sprint’s completed work will add to the Increment at the end of the Sprint. An important distinction is that the Increment must be in usable condition – meaning it can be broken is the current Sprint’s addition to the Increment renders the product unusable.