Who is Daenerys Targaryen from A Dance with Dragons: A Song of Ice and Fire: Book Five and what is their importance?

Daenerys Targaryen is the self proclaimed Queen of Westeros and Queen of Meereen. She is the only child of Aerys II Targaryen and Rhaella Targaryen, and as such, she is the sole heir to the throne. Dany is described as a striking, young woman with violet eyes and silvery blond hair.