How the humble paperback helped the United States win World War II
During World War II, American soldiers were provided with specially designed pocket-sized paperbacks called the Armed Services Editions. These books, totaling around 120 million copies, were intended to help soldiers pass the time and remind them of what they were fighting for. The program aimed to promote the free exchange of ideas and contrasted American ideals with Nazi book burnings. The books were distributed for free and boosted the popularity of certain authors.
Source: indiatimes.com