Until the release of Dynamics NAV 2009 there was only one client available on the Windows platform. After the release of the Dynamics NAV 2009, Microsoft introduced the RoleTailored Client. Following this the old client is referred to as the Classic Client. With the release of Dynamics NAV 2013 the classic client has been discontinued and the RoleTailored Client is now just called the Windows Client.
The main differences between the two is that the classic client is based on the traditional two tier concept, and the new client on a three tier concept. The two tier has two elements: the client and the database server (either native or SQL Server). The three tier also has an application server between the database and the client.
The RoleTailored client was completely re-written as a .NET application and introduces many new features to the NAV user experience (UX) including a Role Center page (that displays stacks of documents representing the number of items that need to be handled such as open sales orders), Charts, Outlook Parts, and extensive Personalization features. Many of the personalization options previously required a developer, but can now be done by the individual users.
Pages in the Role Tailored client can be exposed as Web Services.
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