Backlinks are the hyperlinks that point back to your website. You can say incoming link to your website. It is one of the metric for the raking of a website. A website with higher backlink tend to rank higher in search engine including Google. It like relationship among pages on internet.
Backlinks are extremely useful to search engines because it give an indication that your website is popular one. It’s like a vote for your website. It shows that your website is worth to visit. It is important to create backlink from quality sites.
Google optimization is based on the premise that the more people that like your website and the higher ranking it deserve in search result.
Generally backlinks are classified in to two types:-
Do follow links
Do follow is something where “no-follow” tag are not using. This link is very powerful and you will see the result within a couple of days. It will ranked you higher in search ranking. you can create do follow link in many way.
No follow links
No follow is something where a tag is use call “no-follow”. A good example of no follow links is social share. Those link are good for getting traffic but they don’t have any value to to ranking your site. When you are adding “ref=nofollow” to any link it means that you are telling Google not to follow that link.
For example, your niche is about fishing and you are creating backlinks from Gardening. This is going to be useless. Your goal should be from relevant site.