HOW can i GET Backlinks

search for do follow blogs and comment on them.  Make relative and subjective comments

do follow blogs??

DO FOLLOW BLOGS??

Search for blogs with commentLuv commenting system or intensedebate commenting system.  They are do follow blogs

what is the use of backlinks?

None that I can think of except for rankings 

As far as I know, backlinks are like advertisements we don't pay for. Your blog gets free advertisements at different places over the internet. That does increases your blog's popularity and viewership.

you need to spend some money to get authority backlinks...

@Vishal: What do you mean by spending money to get authority backlinks? Can you please elaborate?

As far as I understand, this can be done with authoratitive publishing too, which means that whatever niche you're writing in, you should be pretty good at that, and you'll get the attention of the readers as well as backlinks. Though it will take some time, it is one sureshot method to get quality backlinks. It all depends upon the content of your blog.

CK you can buy quality and authorative backlinks from many online sites.  Try Fivrr if you wish.  They take money and give you back links.  You can also buy FB likes if you want

I have never done it but I know people who have.  

Here is "how this Paid Backlink Works"

Some one pays 10-100$ for some review or guest post on your pr and da blogs. Backlink seller accept that money and in return gives buyer one post with 1 or 2 dofollow backlinks to their blog. It is highly trusted and used by many startups or small business. Since it requires less time to get more backlinks from your choice of website. and Trust me these are far more better and faster than guest posting..

that backlinks was'nt gud bro

i want quality backlinks

Write guest post in shoutmeloud you will get a quality backlink (that is if Harsh allows it)

Gokul Gir  -> that's Incorrect... now days Even I don't allow free guest post on any of my blogs...One thing I know "If you are good at something don't do it for free"

I have  few pr and da blogs and guess what one of my blog made $500+ in two months from Sponosed post... (I know this is against google tos but who cares "If some one is buying then I m selling" that's it... and Still Google has not any means to measure difference between paid post and Guest Blogging

Search for blogs which publish guest posts. In every published guest posts you can add links to your blog. Number of links depends on the TOS of the guest blog. Another source is ezinearticle.