Merge tool can be used to merge two or more entities into a single layer. All merging entities must be of the same type (points, lines or polygons). Caution should be exercised because this tool does not modify the geometry of the entities, even if there is overlap. The tool is located at the following address:
ArcToolbox > Data Management Tools > General > Merge In the Merge tool pop-up window, you will find the Input Dataset section where all the layers to be merged are selected (remember that they must be of the same geometry). In the Output Dataset section, a name and directory are assigned to the resulting layer. In the Field Map section, fields of the participating layers are added, renamed or deleted. An example is shown in Figure 36, where two layers of separate polygons are located on the left and the merging of the two layers into one is shown on the right.
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