Von Neumann Architecture simply refers to the type of computer setup that we have always talked about. Some of the key features are:

• Data and instructions are stored in the same memory (RAM).
• The CPU executes one instruction at a time.
• Registers store actively used data (Accumulator, Memory Address Register (MAR – stores the location of the data needed), Current Instruction Register (CIR – stores the location of the next intruction to be executed)).

This website provides more detail about Vonn Neumann and is a great resource for other topics too.