Periodicals are almost always published in softcover and sold by subscription . Most newspapers and popular magazines are also sold in stores and at newsstands. Full-text of some periodicals is now available over the Internet. Back issues may be available on microfilm or microfiche . Most newspapers and popular magazines contain advertising, but scholarly journals usually do not.
Periodicals are more ephemeral than books.
Title changes are frequent. Scope may shift to reflect changes in editorial policy. Because newsprint is bulky , the WCSU Libraries keep only the most recent two months of newspaper titles in print . The backfiles are usually available on microfilm . Published daily or weekly , newspapers often provide the most current information available on a topic.