Final answer:
When creating a pull request from a user story, you compare the source branch (where the user story is implemented) with the target branch (where the changes will be merged into).
Step-by-step explanation:
When you create a pull request from a user story, you are comparing the branch where the user story is implemented and the branch where the changes will be merged into. The branch where the user story is implemented is typically the source branch, while the branch where the changes will be merged into is typically the target branch.
For example, let's say you have a project with two branches: 'feature-branch' and 'main'. You create a pull request from the 'feature-branch' (source) to the 'main' (target) to review and merge the changes made on the 'feature-branch' into the 'main' branch.