diferencia entre el índice, seguir o seguir

<meta name="robots" content="index, follow"> 
<meta name="robots" content="noindex, nofollow"> 
<!-- 
Follow means : page will be crawled.
No Follow means : page will not be crawled.
Index means : your page show in search results.
No Index means : your page does not show in search results.
-->
Mushy Manatee