When you're looking for data for your map project, it's really important to be able to evaluate it correctly and to know what it is that you're looking at and to be able to decide whether that's going to be a useful dataset for what you want to do. So, in order to do that, we need to know about metadata and the way I always think of metadata, I hate to say this because I know there's some people that love metadata, librarians I know will go on for hours about it, but to me, it's one of those topics that's boring, yet very useful. So, stick with me on this and I think you'll see what I'm talking about for better and for worse. So, what is metadata anyway? All it is, is the information about a dataset. It's not the data itself, it's not the measurements or the points or the lines or whatever it is that's inside the dataset, is the information about that dataset. We need that to determine if that data set is going to be suitable for whatever it is that we want to use it for. So, it can be things like the purpose of the data, why was it collected? Where did it originate? How was it created? What scale was it created at? What map projection was used? What's the geographic area? What are the attributes that are included in the table? How do I go about getting that data? If I wanted it, do I have to pay for it? Is there a cost associated with it? And is their contact information to try and find the data or if I want to get an update later or whatever? So that's what we're talking about. Is the information about that dataset. A good analogy when thinking about metadata is that it's like labeling on a package of food or can assume. What's in it? Is it good for me? In both cases, whether it's the labeling on the soup can or the metadata about your dataset, is that you're trying to make an informed decision about the contents of that thing. So, is that something that I want to consume whether it's consuming its food map data in your map or whether it's to consume yummy soup that will make you full? Good idea. So, that's really what metadata is about is, that if you don't have metadata, if it's missing or no one ever bothered to create it, then you can't really make an informed decision and then you may be using data that's flawed or out of date or shouldn't be used at all to begin with. So, if you don't have the metadata, then you're not making a good decision. And yes, just for fun, I figured if I'm going to show us a can of soup, I might as well make it a Warhol right. Just for cakes, why not? The thing about metadata is that it's kind of tedious to input, to type all that information in. In the old days, what would happen is that metadata might be in a text document or a word processing file and every time a new file was created, like a new GIS layer and you think there could be hundreds of them or more thousands, so you work for a CID or something, some person would have to say, "Oh! We created a new map layer. Okay, I've to fill up this documents, and I have to include who I am, when it was created, what it was created for and all this stuff." So, often what would happen is that that metadata just would not get created, was too time consuming, too tedious, nobody wanted to do it, and so a lot of times and this is still true for a lot of datasets today. That metadata just doesn't exist and that's problematic, is that you can't really know what you're getting, and you may not even know that that data exists, and that can be a problem as well. So, what Ezri did when they first created ArcGIS, was they tried to find a way to build metadata in an automatic way as possible. So, when a new dataset is created by ArcMap or catalog, by default the software will create metadata that's actually built into the files. So, it's not in some other text documents somewhere else. It'll build that into the file and it will automatically populate as much of that metadata as possible. You can't do all of it, but you can set up a template to have it fill in certain things, and it will also detect things like the the geographic extent, which it can figure out on its own. What fields are included in the attribute table, that's already in the data so, we can fill that kind of information in. So, it's really handy that they've done this. So, if nothing else at least there's some basic metadata that should be included in any dataset that's created by ArcGIS. So, here I am in Arc Catalog and you'll notice that for a particular dataset, in this case, I'm looking at ONrte.shp, so this is a shapefile. That there's three panes across the top of the three tabs, and so this one here has contents and so I got a little thumbnail here that shows me just like a quick kind of image of what the contents of that data set are. This is a better version, this is a preview of that dataset, so you can actually see what's in there, and the third tab is called description, but really what that is is the metadata, and here for this dataset, this is from a company called DMT spatial, and they were very good about producing really good metadata. I think, I'm assuming because they sell this data for a lot of money and they're trying to add value to their product for their customers, so they make sure that the data's well documented. So, here we can see that there are fields for things like, well first we have tags and see there's tags there, and this is routing data for navigation and so on. So we have things like root hierarchy, time, distance, road length. There's a field here for summary which they didn't include, but they did include a description. They say the root file is the core routing layer based on the Ken maps root layer. There are no credits here, but they could have included them. There's limitations in terms of an end user license agreement. There's extents in longitude and latitude, so you know geographically what part of the world this includes. If we scroll down, there's things like scale range, like the recommended scale at which this should be displayed. There's some other things in terms of keywords. Citation information, this is a pretty old dataset, so it was first created in the year 2,000. This one was last updated in 2012. If we keep scrolling down, we have more information that will go through all of this, but you can see there's things like the processing environment that was created and even that like the operating system that was used, the spatial reference, the datum that was used, we have information on the field properties, the lineage of it. So, in other words, when was first created? When was it updated? That kind of thing and who to contact in terms of distribution. So, we have contact information, there's a phone number, there's a mailing address, there's an email address. That's really useful to know. If I find something wrong with that data and see if there's a newer version of it, I know who to contact and that's all built in to the metadata inside the shape file inside the ArcGIS environment, which is great. Insight ArcGIS you can edit metadata, so you don't have to go with just what's been created by someone else or if you're creating your own feature classes, you want to populate that metadata you can. So, these are just fields in a form that you can fill in. You can just type that in and say save up here, and then you've updated your metadata. So, it's not that it's a difficult process. It's not something that's complicated, it's just time-consuming and much face it's a little bit tedious. There are different metadata styles available. I don't claim to be an expert on all the different styles. There are people that spend a lot of time on this, I am not one of them. I'm kind of the person that I need metadata for certain things and so, I know enough about it to find it and use it. I'm not someone that spends a lot of time thinking about it otherwise, but maybe you are, maybe it's something you'd be interested in. So, there's ones like the North American profile that are ISO standards, there's one that FGDC, there's different ISO standards and so, if this is important to you or if you find that there's something missing from one that's included another, you can set that standard inside the ArcMap environment or GIS, and then use that for your organization or if you want to make sure that you're meeting the standards of, say for your client that you're sending data to or whoever it happens to be. Just to give you a sense of the volume or complexity of metadata. This is a screenshot from a website for the Federal Geographic Data Committee. This is slightly out of date now, but I really like this example. Is that if we scroll down here, you'll see that there's actually a PDF that you can download of the metadata standards. In other words, this just describes all of the fields that can be filled in for a form for one metadata file. So in other words, you've just created a GIS layer, you want to fill in the metadata, you go find this PDF you say, "Okay. So what do I have to fill in to complete this metadata?" So, let's just have a quick look and oh! It's 300 pages long. That's just describing the standard for the metadata, which is kind of crazy. Now, I'm not criticizing the people that made this up. They have good reasons for this. There's all kinds of different scenarios and organizations that may need metadata for different reasons and they have to anticipate every possible one. So, I get that, but the thing I'm trying to get across here is that, for your average user like someone like me or possibly you, that's a bit overwhelming, and the problem is that often people say, "Oh! Take with it. I'm not going to bother filling any of it, and I'm not going do any metadata at all", and that's a problem too. But then, what's happening is that your data is actually losing value, if it's not properly documented. People don't know that it exists and they don't know what it's about or how to judge it and so won't get used as much, and data that doesn't get used as much, has less value than data that gets used more. If you're curious about accessing metadata from within ArcMap, all you have to do is right-click on a feature class and select "Data", "View Item Description" and that will bring up a version of the same metadata that you can access through our catalog. So, this is what it would look like, viewed in ArcMap.
