A niche market is a focused targetable portion (subset) of a market.

By definition, then, a business that focuses on a niche market is addressing a need for a product or service that is not being addressed by mainstream providers. A niche market may be thought of as a narrowly defined group of potential customers.
Niche blogging is the act of creating a blog with the intent of using it to market to a particular niche market. While it could be argued that all blogs are, in some form, a niche blog, the term as it applies to marketing refers to a particular kind of blog.

Neither blogging nor niche marketing is a new concept. However, only in recent years has the concept of a niche blog come into being.

Usually, niche blogs will contain advertisements of some sort (pay-per-click or products or both). In some cases, the purpose of the niche blog is to incite the reader into visiting another website which may then attempt to sell the reader a product or service.
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