Coding under version control means lines get added or changed since the last commit. Sometimes you want to spot what you've changed without the disruption of going to a diff dialog.
Time to get in the gutter. Adding some changes.
The IDE marks adds and changes in respective colors in the "gutter" to the left of the editor. You get colored stripes in regions that are uncommitted. This makes it easy to scan and see changes -- adds in one color, changes in another -- since the last commit.
Clicking in the gutter beside the line, on the decoration, brings up a popup toolbar with some useful VCS operations for that changed line:
Navigate to prev/next change
Revert that change
Copy the previous revision for that line to the clipboard
Move the change to a different changelist