change picture names

Author: vmoratti

Wireframe/index.html

@@ -22,7 +22,7 @@ <h1>Wireframe</h1>
   </header>
   <main>
     <article>
-      <img src="README-image.png" alt="an image showing an example of a README file" />
+      <img src="placeholder.jpg" alt="an image showing an example of a README file" />
       <h2>
         What is the purpose of a README file?
       </h2>
@@ -35,7 +35,7 @@ <h2>
       <a href="https://en.wikipedia.org/wiki/README">Read more</a>
     </article>
     <article>
-      <img src="wireframe.png" alt="an image showing a hand drawn sketch" />
+      <img src="wireframe.png" alt="an image showing a hand drawn sketch of what a wireframe looks like" />
       <h2>What is a Wireframe?</h2>
       <p>
         A wireframe is a visual guide that represents the skeletal framework of a website or application.
@@ -44,7 +44,7 @@ <h2>What is a Wireframe?</h2>
       <a href="https://en.wikipedia.org/wiki/Wireframe">Read more</a>
     </article>
     <article>
-      <img src="branch-image.jpg" alt="an image showing a Git branch" />
+      <img src="branch-image.jpg" alt="an image showing a  diagram of a Git branch" />
       <h2>What is a Branch in Git?</h2>
       <p>
         A branch in Git is a lightweight movable pointer to a commit.