add summary and link for git branch article

Author: remimarcelle

Wireframe/index.html

@@ -49,8 +49,8 @@ <h2>What is the Purpose of a Wireframe?</h2>
           />
           <hr />
           <h2>What is a Branch in Git?</h2>
-          <p>[summary goes here]</p>
-          <a href="#">Read more</a>
+          <p>A branch in Git is a lightweight pointer to a commit. It allows developers to work on different versions of a project simultaneously without affecting the main codebase.</p>
+          <a href="https://git-scm.com/book/en/v2/Git-Branching-Branches-in-a-Nutshell#:~:text=A%20branch%20in%20Git%20is,Note">Read more</a>
         </article>
       </section>
     </main>