VMware Workstation, VMware Player and VMware Server seem like redundant products. However there are quite a few distinctions, that are quite apparent from their names already.
VMware Workstation is intended for “desktop use”, for a user who creates and edits Virtual Machines and uses them on his/hers desktop. It has features useful for product development that no other VMware product has such as integration with MS Visual Studio or VM teams, where the network between virtual machines in the team can be specified, including bandwidth and packet loss. VMware Workstation usually gets the new virtual hardware releases first and supports the widest guest OS range. It is optimized for interactive use and has some Direct3D (DirectX 9) and OpenGL capabilities. Workstation is not free. More information:
VMware Player is a stripped-down version of workstation, so it offers the same virtual hardware as Workstation. VMware Player 2.x and newer is free for non-commercial personal use only while Player 1.x had no such restriction. In the latest version it can both create and edit virtual machines while it earlier could only possible to run pre-built VMs. The performance of VMware Player is very similar to the performance of VMware Workstation. Even though Workstation 8 was released in September 2011, we are still waiting for VMware Player 4 to be released. For more info see here:
VMware Server is meant for creating and editing virtual machines and running server-like loads. It is optimized for IO rather than interactive use on the local terminal. Desktop intensive (graphical) applications will not have too good performance when viewed through the interface provided in VMware Server as all requests go through the network (even when you’re working locally). Server usually provides older or same generation of virtual hardware as Workstation or Player. Server is a free product, but note that VMware Server is declared End of General Support at 06/30/2011. More information:
VMware Server cannot be installed at the same time with Workstation/Player. This is most likely due to conflicting, different kernel modules and cannot be circumvented.
Note that even if this article says that the intended use is something, this does not mean that the product could not be used for something else. Just don’t expect Player to be a good Server or that you can play games on Server.