Add proper Summary section

common-flow.md

@@ -34,6 +34,20 @@ Terminology
 - **Release Branches** - Used both for short-term preparations of a release, and
   also for long-term maintenance of older version.
 
+Summary
+-------
+
+- The "master" branch is the mainline branch with latest changes, and must not
+  be broken.
+- Changes (features, bugfixes, etc.) are done on "change branches" created from
+  the master branch.
+- [Rebase early and often.](https://i.imgur.com/1RS8x2d.png)
+- When a change branch is stable and ready, it is merged back in to master.
+- A release is just a git tag who's name is the exact release version string
+  (e.g. "2.11.4").
+- Release branches can be used to avoid a change freezes on master. They are not
+  required, instead they are available if you do need them.
+
 Git Common-Flow Specification (Common-Flow)
 -------------------------------------------