Question 1

User Story

Accepted Answer

A User Story is a story told by the user (of the product) of her/his challenges, or opportunities.

The original intent of the User Story has been that a User Story is to be told not written.

A User Story card is a promise for further communication. Communication that should happen between the Developers and the Customer or Stakeholders to create a shared understanding of the user's needs.

Further Reading:

Writing Effective User Stories Becoming User Centric with User Stories

Also see:

Product Backlog Item, Spike, Technical Debt, Splitting User Stories

Question 2

WIP Limit

Accepted Answer

The maximum amount of Work-In-Process (WIP) that can be pulled in for processing / implementation within a workflow. This is a limit on the total amount of items that can be in process.

The purpose of having a WIP Limit is to increase the focus on the flow of value. Due to the limits on WIP, the remaining work items can be either Waiting to be Picked up or Completed (Done).

In a Scrum environment, to improve the flow of value delivery, it's recommended that the number of work items in progress may be lesser than the number of developers available to execute the work items.