Final answer:
The main difference between sequential and combinational circuits is that sequential circuits have feedback loops and memory elements allowing them to save and process information over time, while combinational circuits do not, working solely based on current inputs.
Step-by-step explanation:
The primary distinction between sequential and combinational circuits in computer architecture is that sequential circuits have feedback loops, which allow them to store information over time, while combinational circuits do not have these memory elements. In essence, combinational circuits perform operations that are solely dependent on the current input values, lacking any form of memory. On the other hand, sequential circuits can 'remember' input states thanks to their memory components, which allow them to exhibit behaviors that depend on both current and previous inputs.
Combinational circuits output results purely based on the current inputs, without any capacity to consider historical data. Sequential circuits, conversely, can capture and hold data in their memory elements, which introduces the concept of 'state' to a circuit. This state enables sequential circuits to perform more complex tasks that require a history of what has transpired previously, distinguishing them from their combinational counterparts which can only work in the 'present.'