Link building simply means to build links to your site for seo(search engine optimization) and traffic purposes.There are many uses and advantages of link building and it is very important for seo because the number of links pointing to a particular site increases the traffic as well as help search engine crawlers (bots) to index your content and increase your search engine ranking.
What is Back links:
Back links are the links that points to your site from some other site and building back links is called link building.
TYPES OF BACKLINKS:
The links pointing to your site/blog can be of two types:
1. Do follow links:
These are the links that has do-follow tag or simply not tagged with no-follow.This type of links allow search engine crawlers to index your blog and they help in increase your search engine ranking and page ranking.
2. No follow links:
These links have no follow tags in their html codes and guides search engine bots not to index the link.
How to create backlinks:-
There are several ways to create backlinks(do follow) that include commenting on coment luv blogs (i.e do follow comment blogs),guest posting,writing articles on article writing sites such as wikipedia,triond,hubpages etc and adding a signature to a discussion forum etc.
You can also create no follow backlinks easily but you can only get traffic from that backlinks.
Also note that always create backlinks with anchor text with your targeted keywords to attract more targeted visitors and it also help in search engine ranking.
You may also like:step by step guide on how to create a free blog on blogger.