Hi Robert,
Q) So Does WebGIS meant it is mostly related to ArcGIS online?
Not quite. Web GIS is a pattern for delivering GIS capabilities and is at the center of Esri’s strategic direction for implementing GIS as a platform. The key concept behind Web GIS is that all members of an organization can easily access and use geographic information within a collaborative environment. Analysts still provide technical GIS expertise in the traditional sense, but other staff in the organization with little or no GIS knowledge can also benefit from and contribute to the organization's GIS platform. Web GIS leverages existing GIS investments and makes them discoverable and more accessible. It provides a platform for integrating GIS with other business systems and promotes cross-organizational collaboration. Consequently, Web GIS extends the reach of GIS to everyone in an organization, enabling better decision making.
At the center of the Web GIS pattern in the ArcGIS platform is the generic concept of a "portal" that represents a gateway for accessing all spatial products in an organization. The portal helps organize, secure, and facilitate access to geographic information products. Client applications on desktops, web apps, tablets, and smartphones interact with the portal to search, discover, and access maps and other spatial content. In the back-office infrastructure, the portal is powered by two components: GIS servers and ready-to-use content.
The ArcGIS platform offers two deployment models for Web GIS. ArcGIS Online, the cloud-based offering, has a software-as-a-service (SaaS) deployment model. All components are hosted in the cloud. There is no hardware infrastructure for an organization to maintain because Esri manages and maintains ArcGIS Online. Alternatively, there is an on-premises model with ArcGIS for Server, which includes Portal for ArcGIS.
To learn more about Web GIS, Esri has published an online book here:
The ArcGIS Book
Hope this helps,
