eBooks are becoming popular because they are a lot less expensive than paper books. A lot of them can also be downloaded for free. Another reason for their popularity is their eco-friendliness. Their production does not require paper and hence they do not harm the environment. Consequently, many people now prefer eBooks to paper books. The fact that they do not occupy physical space is another factor attracting readers. Also, unlike printed books, eBooks can be updated any time. As a result, when facts change or new information arrives, eBook publishers can instantly launch a revised version. In the case of paper books, readers have to wait for a new edition to arrive and this may take years. eBooks also possess other features like the option to increase font size or highlight text. They are highly portable too. Thousands of eBooks can be stored on a handheld device like a tablet or smart phone.