...
They are parts of the html of the page that are invisible to visitors but provide information for other services (such as Facebook). For example, the meta tags our system adds to action pages when using the social networking tools look a little like this:
| Code Block | ||
|---|---|---|
| ||
<meta property="og:image" content="http://www.engagingnetworks.net/profiles/engagingnetworks/themes/engagingnetworks_theme/images/sharelogo.gif" />
<meta property="og:title" content="Engaging Networks" />
<meta property="og:description" content="Raise money. Win campaigns. Nurture relationships with your supporters. Our flexible, customisable web tools help your non-profit change the world." /> |
The reason this is important is because Facebook only saves the details the first time the page is shared. To save loading time later, next time someone shares a page they just retrieve the details from their database (this type of process is called cacheing).
...
Like Facebook, Twitter can cache images against a link. See this article for more information on how to make it work.