Jack London (1876—1916) was an American novelist, journalist and social activist. Pioneering the genre of magazine fiction and prototyping science fiction, he became one of the first writers, who gained worldwide fame and a large fortune. This book is an autobiographical memoir full of London's experiences living as a hobo during the economic crisis in the United States, hopping freight trains, begging for money or food, and making up stories for the police to avoid prison term. He also describes his arrest and the time in the thirty days in the Erie County Penitentiary, a place of "unprintable horrors", as he mentions in the book.