Quirky URl, Something I Am Missing?

Bear my ignorance please!

I always believed there were not so much Top Domain Name Extensions. What I knew were .com, .net,.edu, ect. And I was quit happy with all of those! (ignorance=happiness?)

Until recently I found more and more companies are adopting strange domain extensions like: htt开发者_如何学JAVAp://del.icoi.us, http://bu.mp... and I was totally puzzled. What does it mean? Obviously what I care is SEO significance, but I am also interested in other related aspects, like what is it differences between well-known extensions? for ordinary users? It seems clear that those new extensions are quit easy to write and memorize, does it mean I should buy domain names like bu.mp or http://i.i?

Thanks for your time?

.us and .mp are country extensions. See here a list of those extension.

If you should register domains like bu.mp is up to you. I found out that here in The Netherlands people (ordinary users) find .nl and .nu confusing. I always advise to register the .nl as well if clients want to use .nu So the well-known extensions still have their value.