The primary client for Dynamics 365 is the web browser. The Dynamics 365 for Finance and Operations client supports many browsers, such as Internet Explorer, Microsoft Edge, Google Chrome, and Safari. 

The following are the key highlights of the browser client:

• Use of pure web technologies: HTML 5, CSS, and JavaScript.
• All communication is via HTTPS, using the RESTful protocol in the JSON data format.
• All code runs on the server within the context of the ASP.NET web app.

From an architecture point of view, the following diagram shows how the browser and the application server interact when the user interacts with Dynamics 365 for Finance and Operations in a browser:

The following steps describe the interaction between the browser and the application server, as shown in the preceding diagram:

1. As the very first step, when the user browses the application page, the user gets authenticated and redirected to the home page of Dynamics 365 for Finance and Operations. If the user is using Dynamics 365 for Finance and Operations for the first time, then the application form engine is requested and cached by the browser.
2. When the user navigates to a form within Dynamics 365 for Finance and Operations, the browser sends the form request to the server.
3. In response to the form request, the server returns precompiled form resources. Form resources are rendered by the browser and client form engine and then cached locally by the browser.
4. Now, the changes made by the user on the form—such as changing the data, and clicking a button—are synchronized between the client and the server, using delta changes.