# Change value descriptions

OS MasterMap COUs (Change-Only Updates) contain a change history attribution:

| Value                                                                                        | Description                                                                                                                                                                                                                                                                                                                                                                                                       |
| -------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| New                                                                                          | This is a new feature in the database.                                                                                                                                                                                                                                                                                                                                                                            |
| <p>Position</p><p><em>(Note: This is no longer used in current revision process.)</em></p>   | Feature has changed geometry and / or position due to an improvement in its absolute accuracy; that is, its relationship to the National Grid (relevant for the positional accuracy improvement programme which was completed in 2006). This type of feature change is not associated with real-world change.                                                                                                     |
| Modified                                                                                     | <p>The feature has been edited by an operator. Used in the following cases:</p><ul><li>The geometry of a topographic feature is changed following real-world change.</li><li>The geometry of a non-topographic feature (for example, inferred link or BoundaryLine feature) is changed.</li><li>A cartographic symbol feature is repositioned.</li><li>A CartographicText feature is repositioned.</li></ul>      |
| Software                                                                                     | Feature has been adjusted by an automatic software process. Includes geometric adjustment, cleaning, squaring, paralleling (text and lines) and reversing direction of digitising.                                                                                                                                                                                                                                |
| Reclassified                                                                                 | The descriptive attributes of a feature have changed. The feature code may have changed.                                                                                                                                                                                                                                                                                                                          |
| TextChange                                                                                   | <p>Text string of text feature has changed. Applied to text features where the text string has been:</p><ul><li>Modified for a minor change in spelling, due to original error or name change, where text string is a distinctive name.</li><li>Modified for changes to a descriptive name, due to original error or change of specification.</li><li>Modified by the addition or removal of an accent.</li></ul> |
| Restructured                                                                                 | <p>New line feature(s) have been created from parts of existing feature(s). Applied to line features where:</p><ul><li>The feature is split into two or more features.</li><li>Two or more features are joined together.</li></ul>                                                                                                                                                                                |
| Attributes                                                                                   | Applied to features that have had only attributes changed, except those covered by TextChange and Reclassified values.                                                                                                                                                                                                                                                                                            |
| <p>Incomplete</p><p><em>(Note: this is no longer used in current revision process.)</em></p> | The feature is incomplete. Identifies an incomplete line feature or an area that relates to the incomplete feature returning from a revision process. Incomplete line features are not used to construct polygons.                                                                                                                                                                                                |


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