Note that the process is iterative and may require re-evaluation of some of the previous steps. The process of data capture must involve both spatial and attribute data. If they are considered separately, then more effort usually is required to integrate both components within a GIS database. It is better to consider both components in planning the capture process to ensure that appropriate IDs and tags are assigned to enable attributes to be correctly attached to the appropriate spatial units. The process of manual entry can be sped up through by-passing the intermediate paper records and directly recording data through laptop computers in the field, electronic surveying instruments, automated GPS position recording, etc.
Most attribute data is entered via a keyboard into a database.
Often, much attribute data exists prior to the GIS being built. In terms of volume, usually the vast majority of a GIS database consists of attribute data. The entry of attribute data and its pitfalls is well known and hence we will concentrate primarily on the spatial component of geographic data. It is owned by the U.S. Department of Defence. Z is a bit worse Differential GPS - correct using base station data.