Offers a wide range of input and output image formats. Has an extensive choice of coordinate systems and transformation methods to work in. The most common types to choose are either point or polygon. Point allows vector points to be placed on a map to mark single locations. Polygon is used to draw vector areas on a map. Polygon is often used to trace features on a map or mark boundaries. The best one to choose if using our georeferenced maps or WMS layers is the British National Grid, OSGB 1936 (EPSG:27700). Type in the Field Name column to add further fields for information you want to contain in the Shapefile's database. When you add a field, choose what type of data it will contain by selecting a format from the Data Type column. Use the 'Add Data' button to add any georeferenced base maps or layers that you want to use as a reference for creating your Shapefile. Your Shapefile and maps you've added will appear as layers in the Table of Contents on the left hand side and will be displayed in the workspace. (At this point you will not have added any information to your shapefile, so nothing will appear in the workspace showing your shapefile.) How you draw your Shapefile will depend on which Feature Type (point, polygon, polyline etc.) you selected when setting it up your Shapefile in ArcCatalogue. Remember to also use the Zoom and Pan tools to navigate within the workspace to help you mark points and trace features of the georeferenced base map you are referencing. Source.