What defines a distributed system?

A distributed system is defined by the sharing of resources across a network of interconnected computers. In this model, multiple computers work together, often in different physical locations, to achieve a common goal or to perform collective tasks. This configuration allows for enhanced resource utilization, fault tolerance, and scalability, as the workload can be distributed among various nodes. Each node in a distributed system may operate independently but they often communicate and collaborate to provide coherent services or to process data.

The emphasis on shared resources signifies that these systems can leverage the computational power, storage, and capabilities of multiple nodes, rather than relying on a single central point. This is important because it highlights how tasks can be processed in parallel and how reliability can be increased since the failure of one machine does not lead to the system's complete failure.

In contrast, the other options highlight characteristics that do not align with the essence of a distributed system. For instance, a single computer with multiple users pertains to a personal or multitasking environment, centralized resource management suggests a hierarchical control which opposes the autonomy of distributed systems, and independent systems with no connection do not share resources at all, which fundamentally deviates from the definition of a distributed system.