Web GIS applications can make your spatial data and maps accessible and intuitive to users, regardless of their GIS experience level. By necessity, your concept of each web GIS application is more complex than your end users' view. This section describes all the elements that you must assemble as part of each web GIS application. These elements provide a framework for how you build and deliver GIS to your end users.
Here is a brief description of each:
The web application provides the software interface to the client, and its corresponding tools are used to visualize, interact with, and work with geographic information. It may be an application that runs in a web browser, or it could be a mobile application that works on a GPS-enabled field device or a smartphone
You have a number of application choices that you can use to build each web GIS application for your end users. Often, the right choice depends on the set of functions, tools, and map displays required by the users' workflows. Just as often, the choice of application will depend on the end user and his or her experience using computers and the setting in which the work is done (for example, in the field, in a remote office with slow Internet speeds, and so on).
In web GIS applications, the basemap provides the geographic context for each application. The type of application (for example, hydrology, parcels, electrical utilities, and conservation) often defines the type of basemap that you'll need to use. For example, in a web GIS application aimed at waterfowl conservation, high-resolution orthoimagery would be an appropriate basemap for digitizing wetlands.
The following are some examples of common basemaps:
Because high-quality basemaps can require a lot of time and skill to produce, Esri hosts a series of basemaps that you can utilize in your web GIS applications. However, if you prefer to build your own basemap, ArcGIS Desktop and ArcGIS Pro provide all of the tools necessary for you to efficiently assemble, author, and cache appealing basemaps. See the topic About building your own basemap for more information.
It is important to remember that basemaps tend to be relatively static. In a typical setting, basemaps are updated on an infrequent basis. For example, a transportation network may be scheduled to be updated on an annual basis to account for street network changes in a large metropolitan city. Conversely, a topographic basemap may only be updated on a decennial basis, due to its dependency on a national census or surveying effort.
Operational layers are the small set of layers that you work with directly or derive as the result of an operation (such as a query) in a web GIS application. These layers are often tailored to a particular group of users by a GIS professional. For example, an urban planner uses a smartphone running a GIS application to update the location of manhole covers in a sanitary sewer/storm water system layer.
Operational layers consist of, but are not limited to:
In most GIS applications, users work with operational information (sometimes multiple operational layers) on top of their basemap, which provides the geographic context. At other times, the operational layer is displayed underneath other layers that help provide locational context. For example, when you classify and display ZIP or postal code areas by demographic information, you often overlay these results with transportation lines and place-names to provide locational context.
Operational layers are often dynamic; they are retrieved from the GIS database and displayed during runtime, for example, each time you pan, zoom, or refresh your map. It is common that operational layers work within a focused range of map scales and resolutions. By contrast, your basemaps may be designed for use at a wider range of map scales. For example, basemaps typically enable you to zoom out to much larger map extents.
For more information, see the topic About operational layers.
Web GIS applications often provide tools that perform processes beyond mapping. These tools range from common types, such as finding an address, to more specific types, such as calculating monthly rooftop solar energy potential for a large city.
There are two ways to run your tasks:
Below are some additional considerations regarding how you can use tasks and tools in your web GIS application:
Each GIS application depends on a strong geospatial data management framework that can hold the information used to support your application. This can be one or more geodatabases, a collection of shapefiles, various tabular databases and spreadsheets, CAD files, design files, imagery, HTML web pages, and so forth.
There is a strong focus in the GIS professional community on investing in and building high-quality geographic information. The answers you derive from your GIS can be no better than the quality of the information contained in your geodatabase. GIS datasets must be compiled in unison, harmonized, and integrated to fit together in a geographic framework. Many GIS users invest heavily in the creation and maintenance of their geospatial databases. These information stores are of immense value in addressing a broad range of questions. Strong geographic data becomes more critical when you want to do more than display observations on a basemap.
ArcGIS geodatabases are a critically important data management technology for modeling, organizing, and maintaining rich GIS information to support your work. Geodatabases are designed to support all levels of GIS implementation, from those that support the simplest geodata models to those that are quite sophisticated.
It is worth noting that any of these elements in a web GIS application can be hosted and served using ArcGIS Server . For example, various web services can be accessed and assembled as part of your web GIS application—a basemap service, operational map services, geoprocessing services, geodata services, image services, and so forth.
One of the great strengths of web GIS applications is that you can mash up remote web services with your own local content to assemble your web GIS applications. It is worth the effort to take time to think about how you might leverage your own resources with services from other organizations in your web GIS applications.
