Annotation

In cartography, annotations are text or graphics--in essence, labels--on a map that display information useful to users, such as the names of streets or bodies of water. Annotations essentially can add a more specific overlay of information to clarify the map to the user without overcrowding the map with wordy details. As the user places his/her cursor over a particular area, an annotation bubble can pop-up. These annotations can also provide outside links for the user to find additional outside information. Unlike adding a specific label to the map with a specified size, an annotation allows the user to zoom, pan, or scroll while the label keeps its appropriate size and orientation.

Stored Annotation in ArcGIS
Annotation is one of the primary methods of storing text in an ArcGIS project (the other being dynamic labeling). When using annotation, each piece of text can be individually selected and manipulated. Unlike a label, an annotation does not necessarily need to be tied to a defined characteristic of a feature. Annotations are more flexible, and can be derived from labels but changed individually. They can also be added to a data frame in a map or to the map layout itself, to which they are tied.

Map annotation can be stored either in the map itself or within a geodatabase. If a map project has a unique annotation that cannot be used in other map projects, it is best to store that annotation within the map. If the annotation will be used in future projects, it should be stored within a geodatabase. Annotations stored within a geodatabase may be added to any map, and will appear as an annotation layer in that map's Table of Contents. Geodatabase annotation feature classes are best used if the location of the text is important and will be used on multiple maps. They are stored in the geodatabase as feature classes similar to that as points, lines, and areas.