The first is used to keep track of all the information on the case, such as people, addresses, filings, settings, documents, deadlines and time sheets. The latter is used to locate, manipulate and effectively use data and images. When a document is scanned, it is retained in an image format. It's contents cannot be edited or searched. Whether to use summary indexes of images or OCR the documents is an individual decision that considers many factors.
Some programs provide for both.
Their search mechanism is so strong that even if the characters are not correctly recognized, resulting in nonsensical words, the program can search for a concept and find the right document. Search by word content, author, subject or case and any other index that you create. One of the necessary ingredients to an e-practice is agreements with clients and opposing counsel. These provide, at a minimum, that in the interest of economy and productivity, documents will be submitted whenever possible by e-mail, fax or over the Internet. When paper documents are submitted, a virus-checked disk containing the word processor file will be enclosed to avoid the necessity of retyping.