In A People's History of the United States, how did Howard Zinn describe why he wrote his book?

Howard Zinn's popular text A People's History of the United States, attempts to be what the title claims it as--a people's history.  Released in 1980, it was meant to include women and minorities in American history since they were often left out of mainstream works, especially for undergraduates.  Zinn gathered material for the book over a twenty-year teaching career and he wanted something that was not only relevant to the young men and women in his class, but something that would get mainstream historians' attention.  Zinn's work has been considered controversial especially given his liberal politics, but the book remains popular in that its a history of America which serves all.  Just like Zinn's undergraduate classes, it does not pretend to be neutral.  Zinn's work popularized using race and gender issues to study American history and today many textbooks at the high school and university level have more material about these issues.  
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