About web GIS

A common task that you'll perform as an ArcGIS user is to utilize web GIS and web GIS applications to make your services available to others within and outside your organization. You will design and create these web GIS applications using a wide variety of resources, and your end users will use these applications to address any number of questions, missions, and problems.

This help section serves as a guide for informing you about the advantages of web GIS, what you should consider before designing a web GIS application, how to leverage ArcGIS resources in basemap and operational layers, and options for performing editing in web GIS applications. Links to ancillary topics are provided to help you gain a better understanding of the resources available to you when designing and creating web GIS applications.

What is web GIS?

Web GIS is a type of distributed information system, comprising at least a server and a client, where the server is a GIS server and the client is a web browser, desktop application, or mobile application. In its simplest form, web GIS can be defined as any GIS that uses web technology to communicate between a server and a client.

Here are a few key elements essential to web GIS:

• The server has a URL so that clients can find it on the web.
• The client relies on HTTP specifications to send requests to the server.
• The server performs the requested GIS operations and sends responses to the client via HTTP.
• The format of the response sent to the client can be in many formats, such as HTML, binary image, XML (Extensible Markup Language), or JSON (JavaScript Object Notation).

The web GIS advantage

By utilizing the Internet to access information over the web without regard to how far apart the server and client might be from each other, web GIS introduces distinct advantages over traditional desktop GIS, including the following:

• A global reach: As an ArcGIS user, you can present web GIS applications to the world, and the world can access them from their computers or mobile devices. The global nature of web GIS is inherited from HTTP, which is broadly supported. Almost all organizations open their firewalls at certain network ports to allow HTTP requests and responses to go through their local network, thus increasing accessibility.
• A large number of users: In general, a traditional desktop GIS is used by only one user at a time, while a web GIS can be used by dozens or hundreds of users simultaneously. Thus, web GIS requires much higher performance and scalability than desktop GIS.
• Better cross-platform capability: The majority of web GIS clients are web browsers: Internet Explorer, Mozilla Firefox, Apple Safari, Google Chrome, and so on. Because these web browsers largely comply with HTML and JavaScript standards, web GIS that relies on HTML clients will typically support different operating systems such as Microsoft Windows, Linux, and Apple Mac OS.
• Low cost as averaged by the number of users: The vast majority of Internet content is free of charge to end users, and this is true of web GIS. Generally, you do not need to buy software or pay to use web GIS. Organizations that need to provide GIS capabilities to many users can also minimize their costs through web GIS. Instead of buying and setting up desktop GIS for every user, an organization can set up just one web GIS, and this single system can be shared by many users: from home, at work, or in the field.
• Easy to use: Desktop GIS is intended for professional users with months of training and experience in GIS. Web GIS is intended for a broad audience, including public users who may know nothing about GIS. They expect web GIS to be as easy as using a regular website. Web GIS is commonly designed for simplicity, intuition, and convenience, making it typically much easier to use than desktop GIS.
• Unified updates: For desktop GIS to be updated to a new version, the update needs to be installed on every computer. For web GIS, one update works for all clients. This ease of maintenance makes web GIS a good fit for delivering real-time information.
• Diverse applications: Unlike desktop GIS, which is limited to a certain number of GIS professionals, web GIS can be used by everyone in an enterprise as well as the public at large. This broad audience has diverse demands. Applications such as mapping celebrity homes, tagging personal photos, locating friends, and displaying Wi-Fi hot spots are a few of the many current examples of web GIS.

These characteristics reveal both the advantages and challenges facing web GIS. For example, the easy-to-use nature of web GIS stimulates public participation, but it also reminds you to take into account Internet users who have no GIS background. Conversely, supporting a large number of users requires web GIS to be scalable.