Today more and more people go to websites when looking for information. Although most readers go to websites for news and e-mail, a form. of person-to-person news, or in the form. of chatting, they also read books on the web. It's called electronic book (e-book). Electronic books could revolutionize reading, but people ought to consider their far-reaching impacts as well. 'The e-book promises to cause a slow tragedy on life as we know it', Jason Ohler, professor of technology assessment, university of Alaska Southeast In Juneau, warned the World Future Society, Bethesda, Md. His assessment weighed the pros and cons(赞成和反对的理由) of e-book technology's impact on social relationships, the environment, the economy, etc. Before you curl up(蜷曲) with an e-book, consider the disadvantages. They increase eyestrain due to poor screen resolution, replace a relatively cheap commodity with a more expensive one, and displace workers in print-book production and traditional publishing. E-books make it easy to share data, thereby threatening copyright agreements and reducing compensation(补偿) of authors, as well as creating nonbiodegradable(不可生物降解的) trash. On the other hand, e-books save paper and trees, reduce the burden of the carrying and storing of printed books, promote self-sufficiency in learning, and make reading a collaborative experience online. They also create new jobs for writers and artists and encourage self-publishing. In final analysis, Ohler points out, e-books should gain society's approval if a few conditions are met: make them biodegradable and recyclable, solve the problem of eye fatigue, be sure the 'have-nots' get the technology, and support e-book training in schools and business. In what sense do e-books exert a negative impact on the environment?