Today's reliance on computers for information and storing of data makes it very easy to practice discovery methods in the office, court room, or field. For one thing, digital data can be electronically searched with ease, whereas paper documents must be scrutinized manually. Additionally, digital data is difficult or impossible to completely destroy, particularly if it gets into a network. This is because the data appears on multiple hard drives, and because digital files, even if deleted, can be undeleted. In fact, the only reliable means of destroying data is to physically destroy any hard drive where it is found.

In the process of electronic discovery, data of all types can serve as evidence. This can include text, images, calendar files, databases, spreadsheets, audio files, animation, Web sites, and computer programs. Even Malware such as viruses, Trojans and Spyware be secured and investigated. Electronic mail (e-mail) can be an especially valuable source of evidence in civil or criminal litigation, because people are often less careful in these exchanges than in hard copy correspondence such as written memos and postal letters.