THE ELECTRONIC CHART AND ITS PROVISIONAL SUBSTITUTES (REPRINTED FROM NAVIGATION, VOL 4, PG 177-184, 1996)

This article compares ECDIS (Electronic Chart Display and Information System) with other electronic chart systems based on raster data obtai ned by scanning paper charts. It separates circumstancial or accessory factors - such as the cost, availability of data, and legal status - from the specific differences between the systems as regards functiona lity and performance. ECDIS is a dynamic information system, capable o f integrating information from various sources onto a single display. Thus this system will completely change navigational practices. Raster systems are far from possessing all these capabilities and must be co nsidered to be substitutes or fore-runners of ECDIS, functioning on a provisional basis at least until such time as a significant amount of authorized vector data covering the main areas of navigation are avail able for ECDIS.