Digital EEG (DEEG) is the paperless recording of an EEG using computer-based instrumentation. The data are stored on electronic media, such as magnetic drives or optical disks, and displayed on a monitor. DEEG has many advantages compared to analog EEG including automatic event detection, storage, quantification, and networking capabilities. The flexibility of DEEG allows for changes of recording parameters, such as montage, filters, and horizontal and vertical display scales retrospectively during record review. In this review numerous clinical EEG examples are used to demonstrate how these post hoc changes, particularly reformatting the montage, allow for more accurate interpretation of the EEG.