Pinging is the name of the process used to notify search engines and directories that your website content has been updated. This means search engine spiders can crawl and index your new content at the earliest opportunity.
It is also what a blog does to notify a server that there is new content available. Most blogging platforms, including WordPress and Joomla, feature a ping function. Using this information, search engines specifically used for searching blogs can always present the most recent content that has been published.
Pinging can also be used as a spam technique – known as sping – where spam bloggers create several pages to try and rank for certain keywords, with the pages linking to pages filled with affiliate links or other forms of advertising.