History: Dynamic HTML

• Navigator 2 and JavaScript allowed web pages to be modified on the client
• Navigator 3 exposed img as an object whose attributes could be changed:
  • Download different image
  • Highlight image when mouse runs over it
  • Allowed prefetching of images

  <a href="dhtml1.htm"
    onMouseOver="document.images['logo'].src='up.gif'"
    onMouseOut="document.images['logo'].src='right.gif'">
  <img name="logo" src="right.gif" height=32 width=32><a>

Try Me for some more examples: