Geographic information
In this topic
Once you have an account, you can add geographic information to the portal. This information includes maps, layers, apps, tools, and files. This information may come from within your organization or from the web.
The information that you add to the portal can be shared with the members in your organization to perform a variety of tasks, such as creating maps from data files and embedding them in a website, developing apps that use address locators and other tools, and downloading layers for use in a desktop app. You can also choose to keep these items private so only you can access them.
Maps
Maps are visual presentations of useful spatial information. They typically contain a basemap, data layers, an extent, and a legend. Interactive maps that you find on the web also contain navigation tools such as zoom, pan, place finders, and bookmarks and allows you to change the basemap, for example, from streets to imagery.
The most compelling maps tell stories about trends and patterns over geographic space. For example, they may explain where people are buying homes, where sea surface temperature is changing, or where elephants travel in the summer. When you make a map, you overlay the data that best tells your story. For example, you might choose a topographic basemap and add layers of business data (such as available stands of timber) and reference information (such as boundaries or labels). These maps share information for a purpose; they don't just display data.
Web maps are the most common type of map. These maps can be opened and used in web browsers, mobile devices, and desktop map viewers. Other types of maps include ArcMap documents, map packages, and tile packages.
Layers
Layers are a specific collection of geographic information, such as boundary lines, bird sightings, local imagery, and historical fire perimeters. These are used in maps and apps. They can be hosted on your portal, a GIS server, or referenced from an external URL. There are three main types of layers: map layers, feature layers, and tables.
Map layers
A map layer is a prerendered collection of map cartography organized by location and scale. Map layers can be displayed dynamically or as cached image tiles. Map layers can be managed as part of your content and referenced in a map or application. Map layers include hosted tile layers, map image layers, and imagery layers.
Dynamic maps generate images when requested by the client viewing the map. As you browse the map, new images are generated and displayed. Dynamic maps can include map image layers and imagery layers. Map image layers are based on vector data, which are points, lines, and polygons. Imagery layers are based on raster data, which are a grid of cells commonly used to store imagery and other information captured by satellite sensors.
A cached map is an organized collection of image tiles for specific geographic extents, projections, and levels of detail that are pregenerated on a server. Cached maps support fast visualization of complex maps, since the server distributes the images whenever someone asks for a map. Examples of cached maps include hosted tile layers, map image layers, and imagery layers.
Feature layers
A feature layer is a grouping of specific geographic features. Each feature in the collection has a location, set of properties, map symbology, and pop-ups. Feature layers allow you to execute queries on the features and perform live edits on the features using templates for an enhanced editing experience. A feature layer can be managed as a part of your content or referenced in a map or application. The contents of some feature layers can be downloaded. If the layer you want to add from the web is secured, see Connect to secured services.
Feature collections
Items such as comma-separated values (CSV) files, shapefiles, GPS Exchange Format (GPX) files, and map notes can be added to a map as feature collections. A feature collection is a type of feature layer. Any feature collection you add can be saved as part of the map. You can also save a feature collection as its own item by clicking Save Layer in the layer properties menu. The item will appear as a new feature collection item in My Content and can be shared with others and added to multiple maps.
When you save a feature collection as part of the map, the data is saved as part of the map. Any changes you make to the feature collection, for example, by editing data, are only reflected in the map. The changes are not applied to the original CSV, shapefile, or map note from which the feature collection was derived.
When you save a feature collection as its own item, the data is retained with the feature collection item and not stored as part of the map. Any changes you make to the feature collection item, such as modifying its data, are saved once you click Save Layer. If the feature collection item is used in other maps, the changes will be reflected there as well. If the feature collection item is deleted from My Content, it will no longer be available to others.
Tables
Tables contain a collection of rows and columns, where each row, or record, represents a feature—such as a parcel or power pole—and each column, or field, describes a particular attribute of the feature, such as its square footage, height, and length. Tables can include location information, such as addresses, or no location information, for example, a simple list of names and salaries.
Files
Files are a specific collection of static information such as customer lists, addresses, images, and location information that can be shared with your organization. You can add files from your computer and from the web. You can also publish files as hosted web layers.
Tools
Tools are services that perform an analytical function such as locating streets and addresses, geoprocessing, finding a place, routing, or accessing a geodatabase. You can also add locator packages and geoprocessing packages as tools.
Apps
An app combines maps, data, and tools for a targeted use such as a polling stations mobile app or an Arctic ice flow web app. Apps can be based on templates or developed with APIs. In general, apps are constructed from information in maps and supplemented with additional app-specific customization.
Apps can be hosted as a part of your content or they can be managed independently and added to the website using the app URL. Apps can also include add-ins, a customization file that plugs into a desktop app to provide supplemental functionality for accomplishing custom tasks.