Buffering - Single, Clip, Dissolve and Multiple Ring
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A buffer is an area (polygon) around an object. The object could be a point, line or polygon. If you buffer around a point, then the buffer will be circular (assuming an appropriate projection, with square units). A buffer about a line will be two parallel surfaces with a curvature at each end point. The buffer about a polygon would be outside the polygon and parallel in general to the polygon edge, this is not exactly accurate if the edge of the polygon is very irregular the shape will not be exactly parallel. Buffers can be a single distance away from the object or multiple buffers can be created such as 10, 20 and 30 miles away from a point. Since the buffer created is a shapefile, the properties can be modified with the symbology command, such as making each ring of the buffer a different color.
The buffers created at times will overlap, you can decide to blend the buffer together or leave the overlap. Since the new shapefile created for the buffer it can be used in other geospatial operations. For example if you are looking at the number of people living in a neighborhood, you can look at those living close to that neighborhood as having similar demographics. So you might make a 100 foot buffer around the target neighborhood and include those individuals also in the study area.
The buffers created at times will overlap, you can decide to blend the buffer together or leave the overlap. Since the new shapefile created for the buffer it can be used in other geospatial operations. For example if you are looking at the number of people living in a neighborhood, you can look at those living close to that neighborhood as having similar demographics. So you might make a 100 foot buffer around the target neighborhood and include those individuals also in the study area.