Between to_image and link_to with image_tag

Rails
1

if i use one of this two line:

<%= link_to_image product.image_url, :action => :add_to_cart, :id =>
product %>

<%= link_to image_tag product.image_url, :action
=> :add_to_cart, :id => product %>

i think it will give me the same result ,but is there a different on
use of this two and if yes what?