1. Link-building is a the obtaining links from external web sites to your own to improve both direct referrals (people clicking on the links) and search engine ranking.

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2.Link building explained in simple term means spreading word about your business on the web. On the web, the more you are visible the more popular your business will be.

Link building is an essential part of internet marketing. The internet and sites need links to other sites in order to receive traffic and to give resources to visitors. Good website content will gain traffic organically by website owners using this content as a resource on their own sites. To speed up the process, website owners may promote their sites by the use of search engine optimization (SEO).

Traditional means of doing this are:
• Search engine submission
• Directory submission
• Paid inclusion
• Banner advertising

More recent means of link building evolved as search engine algorythms changed.
These include:
• Reciprocal linking
• Blogging, RSS feeds and
• Social bookmarking
• Article submission
• Press release
• Text link leasing