Electronic discovery ("e-discovery") is the process of requesting, obtaining, and reviewing electronic material that has not been produced through traditional discovery methods. Common types of material include e-mail messages, word processing files, spreadsheets, presentations, address book information, Internet use histories, and files downloaded from the Internet.

Even where hard copy materials have been produced via traditional discovery methods, their electronic version often contains additional information which reveals more than the document itself. This "metadata" is not visible on the printed version but contains information such as revisions, deleted material, and typist information.

A common misconception is that only large corporations with many computer users, centralized file storage, and e-mail servers have electronic information worth reviewing. Virtually any computer that is owned or consistently used by an individual may contain relevant, discoverable data that could be of value in litigation. An individual's computer or PDA may contain exactly the same kinds of material found on a company-owned computer.