A blogger is someone that writes a blog. A blog is an online journal that a writer can use to share his ideas, thoughts, expertise, or interests. Therefore, a blogger is someone that writes his ideas and thoughts online. Blogging is about self-expression. Bloggers write about their lives, their experiences, their expertise, their passions, and their opinions.
Because many do not understand blogging, they expect journalism from bloggers. Bloggers express how they feel about issues. On the other hand, a journalist is someone who writes for a magazine or newspaper, usually writing news items and is required to tell all sides of a story. Journalists are required to be unbiased and to refrain from expressing their opinions in news stories. Journalists are required to have a number of different sources before publishing an article. Objectivity is key in journalism. Blogger can be biased.
Blogging is not journalism. Blogging involves self-expression. Journalism seeks to disseminate facts as unbiased and be as impersonal as possible.
In their pure forms, journalism and blogging are two different professions, though they may have similarities and may overlap.