The only difference here is that you can add multiple distances. So, this is actually a different tool in the same toolbox. So, I just filled them in here, and I made them semi-transparent so you can see what's underneath just to give you a sense of how you can show these and what options might be available. So, you can do anything with them that you would with any other kind of polygon. They are polygons that exist in a new feature class. Especially if you're interested in just being able to show what areas are within a certain distance of an object, then you may want to choose this option. What that will do is, when it creates them, it will dissolve that boundary so that you'll only get the outside part of it. All you have to do is select the Dissolve Type All. You can instead dissolve the boundary for that. So, that's the ring for that library, that's the ring for this library, and so on. You may also notice that it's created a separate buffer ring around each library. I figure, "Hey, why not?" You know you're associating these distances to these objects, why not make it easy for people to see that connection or make that relationship clear? You don't have to do that. By the way, I don't know if you care, but yes, I actually did make the color of the buffer as the same color as the symbol for the libraries. For example, you could think anywhere that's inside that circle, you know is within a distance of 750 meters of a school. There's different ways to think about this. So, as you probably can gather, these blue lines here are exactly 750 meters away from school. So, I want to create a vector buffer at a distance of 750 meters, and this is the result that I get. My output is going to be a new feature class called the buffer_750m, so for 750 meters, and then I'm going to input my linear units here. So, now my input for this is the library points. You just double-click on it to open it, and you'll see this dialog box here. So, if you want to find the vector buffer tool, if you go into ArcToolbox and under the Analysis Tools in the Proximity toolbox, just think of these as like folders, you'll see the buffer tool there. So, here I have some libraries and schools, and we can measure distances from those. So, it's something that I really highly encourage you to make sure you know how to use because it'll come in handy in all kinds of different ways. Distance is relevance to so many different things in geography. You might have a zone of noise pollution around highways, walking distances to grocery stores. Often, for example, there'll be a protected distance to keep cattle away from streams so that they don't contaminate it. Just some examples of applications would be perhaps protected zones around lakes and streams. There are all kinds of reasons why you might want to create a buffer. So, even when you have these elaborate or complex-looking buffers, really, it's just based on these simple building blocks of the software is using. The software is drawing these circles around each of the points, and then rectangles around the segments, putting them together, dissolving it. If we extend this idea to multiple segments, it's exactly the same thing. So, for example, if we created a vector buffer of 100 meters, then this purple outline here as an isoline representing 100 meters, so that anywhere along that line, you know is 100 meters away from the original object. So, it could be elevation, or air pressure, or whatever. It's a generic term that can be applied to a lot of different things. Once the vector buffer is complete, it creates what's known as an isoline. But I just wanted to show it to you so you can kind of visualize how this works. ![]() Now, you don't have to go through those steps yourself. If you think of a line segment, which is essentially two points connected by a line, you can draw a circle, or the software draws a circle, around the point at one end, then at the other, and then draws a rectangle around the line segment itself, and then dissolves that boundary to create the actual vector buffer. How buffers are created is pretty straightforward. ![]() ![]() Distance is a really important aspect of just about any kind of geographic analysis, and a really easy way to measure distances and to show them on a map is to use vector buffers.
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