Update 09_branches.md

lessons/09_branches.md

@@ -13,7 +13,7 @@ author: "Heather Wick"
 
 ## What is a branch?
 
-So far we've demonstrated how Git captures a history of your repository in a series of snapshots, made every time you commit a new change to your repository. But what if we want to make some more experimental changes to our repository? Perhaps there is a bug that needs to be fixed, or a new feature we want to add to a pipeline, but we're not quite sure if these changes will work or mesh properly with our main code. Or, maybe we have a collaborator that wants to make contribuitons, but we want to make sure that we preserve our original repository as-is as a backup before reviewing and incorporating their contributions. For these types of experimental fixes or changes, we can create a new **branch** independent from `main` to make changes to while keeping our `main` safe from any unstable code. This new **branch** will have its own history of commits separate from `main`.
+So far we've demonstrated how Git captures a history of your repository in a series of snapshots, made every time you commit a new change to your repository. But what if we want to make some more experimental changes to our repository? Perhaps there is a bug that needs to be fixed, or a new feature we want to add to a pipeline, but we're not quite sure if these changes will work or mesh properly with our main code. Or, maybe we have a collaborator or team of colleagues that making contribuitons to the same project, but we want to make sure that we preserve our original repository as-is as a backup before reviewing and incorporating their contributions. For these types of experimental fixes or changes, we can create a new **branch** independent from `main` to make changes to while keeping our `main` safe from any unstable code. This new **branch** will have its own history of commits separate from `main`.
 
 The illustration below shows a repository where each commit is represented by a circle and the edges show their linear relationship. Someone has made a new branch, `Some Feature`, independent from `main`. `Some Feature` has some of its own commits, but that history of commits is separate from `main`: