title: what's the difference between image and texture in OpenGL
body: <p>I just start to learn the OpenGL. I was confused by the Image and texture.     </p>
  
  <ul>
  <li>Is image only used to shade a 2D scene. And using vertexes and texture to shade the scene in 3D scene? (I mean in the <strong>operation order</strong> of <code>OpenGL Programming Guide</code> book. First we have vertex data and image data. We can use the image data as the texture or not. When not use as the texture. It's only can be use a background of the scene right. <code>right</code>?)   </li>
  <li>Is texture operation faster than image operation.</li>
  </ul>