please help What is pingback and Trackback and how it work in wordpress??

hi
i want to know what is mean by pingback and trackback and how it works i saw this lot of website that there is not comments at bottom but lot of website pinkback links adding in website to see sourcecode of that page example http://oregoncatalyst.com/29309-dems-tighten-stranglehold-oregon-2.html in this page there is only 17 comments right now but when i click on source of that page and check that lot of website pingback to that website i dont know how they add there on link for comments on that website
so any body can explain how i can do that i mean how i can add my comments on that page with pingback like others people did is there is any plugins for wordpress to do that or what is other way i need to follow to post my pingback link to these blog here is screenshot of that blog source code where is people getting pingback link https://gyazo.com/28563dda326fc344c9c2560b8ff79261 and 100s of other pingback as well so please any body help me and guide me with full details i can do that thanks
and also tel me it is good for seo for ranking ?

Google is your friend here

i did but not properly understand thats why post here

any body else ?

What I understand is you need one good comment option in your site.
AM I right?Correct me.