Conceptually, pingbacks and trackbacks are simple but could prove to be little confusing at the start as it was the case with one of my colleague . He asked me series of questions related to trackbacks and pingbacks to get his doubts cleared. Here is the conversation which I had with him and I hope this would help you as well in case you have any doubts on this topic. His questions are in bold text.What are trackbacks and pingbacks anyway? I know these are the methods of communicating between blogs and are used to notify the blog authors about the inclusion or reference of their article/posts by other bloggers..
As you rightly mentioned above, both of these are very similar in nature yet very differernt. Let’s see this with an example. Let’s say I have read a post on your blog and I would like to write a post on the same topic as is yours. I would like you to know that I have read your post, found it interesting and I have written about the same in my blog (for my reader of course). This is the situation where notification methods like trackback and pingback comes in picture. When I write a post on my blog, I will send a pingback/trackback notification to your blog. Your blogging software, on the receipt of my notification will display excerpt from my post along with a link back to my post as a comment in your blog post. Benifit is that readers of your blog will be able to read what I have to say about your post (by reading my comments sent as trackback/pingback) and my reader will also get to know about what I have to say about your blog. Readers of both the blogs can comment on either of the posts as they know a way to reach other’s post now by means of the link provided. So as I said, they are very similar in their purpose. As a matter of fact, pingbacks were designed to overcome some of the shortcomings in Trackback.

Ok but how do I send a pingback or a trackback?
In WordPress, you just need to link to other blog post in order to send the pingback. When you include a link in your post, WordPress automatically sends a pingback to the linking blog.
Sending a trackback involves little more effort from your side as you need to know the trackback URL of the post. Once you know the trackback URL of the post, you can do the following to send a trackback to a post …

- Before publishing the post, paste or type in the trackback URL in the textbox of trackback section (scroll down and if necessary click on the ‘+’ sign).

- You can include the trackback URL in your post itself but trackback URL should be hyperlinked
- While sending the trackback you can also include an optional excerpt of the post by writing in a textbox which can be found just above the trackback section in the new/edit post page in WordPress admin panel.

How would I find the trackback URL?
The trackback URLs are published by the blog owners and are generally displayed after the content of post and before the comments. Trackback URLs can be displayed in variety of formats like plain text, hyperlink etc. If it is not listed, you can directly ask the blog owner for the trackback URL.

Tell me what goes on at the blog who is receiving the pingback/trackback?
When you send a pingback request to a blog then that blog (referred one) tries to find out the links in your post for its authenticity. If the referred blog software finds the link in yeour post then it extract some text from your post and adds the link along with the extracted text as a comment to your blog post. Same thing happens with the trackback except the fact that if you have included an optional excerpt then the excerpt will be added as comment along with the link instead of the text extracted by the software.

I still don’t understand the difference between pingback and trackback?. Ok, the biggest difference between the two is that pingbacks don’t send any content to referred blog but Trackbacks do. Remember while sending trackbacks you can include an optional excerpt of the post. Second difference is that pingbacks support auto-discovery where the software automatically finds out the links in a post, and automatically tries to pingback those URLs, while trackbacks must be done manually by entering the trackback URL that the trackback should be sent to. Another difference is in the communication method used by trackback and pingback. Trackback uses HTTP Post and pingback uses XML-RPC as their communication technology. Don’t bother about these much

Does all the blogs accepts pingback and trackback?
You can’t make it a thumb rule but yeah most of the blogging software supports pingback and trackback however blog owners can decide whether they want to accept pingbacks and trackbacks. Some choose not to.

Oh, how do I know whether my blog accepts pingbacks and trackbacks?
In WordPress admin panel, go to Options and then click on the ‘Discussions’ tab. If the second options are checked then your blog accepts both trackback and pingback.

Uncheck if you want to do otherwise. Uncheck the first option in case you don’t want to send automatic pingbacks and trackbacks to other blogs by having hyperlinks in your posts to other blog posts.

Is there a way to find out whether a blog accepts pingback?
You can try looking the following code in th HTML coding if the webpage

<link rel=”pingback” href=”http://{{hostname}}/xmlrpc.php” />

where in {{hostname}} is the web address of the blog post.

How would I know that whether the post I am linking to has been pinged or not?
In WordPress, go to the edit post and scroll down to trackbacks (click on ‘+’ sign if it necessary). Here you will see all the URLs which have been already pinged as shown in the following image.

Any thing else which I should keep in mind?
Hmmm, keep in mind that the blog you linking to may not be accepting trackbacks and pingbacks as blog owner might have disabled it. Your trackbacks and pingbacks may or may not be displayed on linking blog posts as most of the time all blogs have some kind of comments spam enabled so your trackbacks and pingbacks could have gone to spam, comments moderation queue and also blog owner might have deleted your comments.

I understand it now but one more question I have. Why would I send a pingback or trackback to anyone anyway?
Hmmm… Let’s say you have published an article after many days of hard work and next day somehow you figure out that the entire article is posted in some other blog without giving you any sort of credit. How would you feel? of course, I will feel bad about it. Yes, same way, if you are talking about an idea or using quotes from someone else’s post, you also need to give them the credit for it by linking it to them. If you use ideas without giving the author its due credit then it is not fair on your side. Michael Stelzner has written specifically about this behavior and he has termed it as Contentjacking in his post Contentjacking: The New Cyber Crime. There is also an intresting conversation on content stealing at on Liz Strauss bog post. Another reason for using trackbacks and pingbacks is to introduce the conversation (blog posts) to more people. When you link (leave trackback or pingback), readers from each blog can reach to other blog post by simply following the links and everyone gets benefited.

Thanks to you for taking time sometime out and explaining to me about pingbacks and trackbacks. I will trouble you again if I get any more questions.

Do post your comments here in the comment sections in case of any doubts / clarification.