The operating system (OS) oversees the execution of multiple applications through a process known as multitasking.

Multitasking is a core feature of contemporary operating systems, enabling several applications to run concurrently on a single computer. This capability is made possible through a combination of process scheduling, memory management, and virtualization.

Process Scheduling

Process scheduling is the technique by which the OS determines which processes (or applications) are granted access to the system’s resources at any given moment. The OS employs a scheduler to allocate CPU time to each process, rapidly switching between them to create the illusion of simultaneous execution. This approach is referred to as time-sharing. The scheduler utilizes algorithms to establish the order of execution, considering various factors such as priority, specific resource requirements, and the amount of CPU time each process has already consumed.

Memory Management

Memory management is another vital component of multitasking. Each application requires a certain amount of memory to operate, and the OS must ensure that each process has sufficient memory to run without disrupting the others. This is accomplished through the implementation of virtual memory, where the OS designates a portion of the hard drive as an extension of the computer’s RAM. When an application is inactive, its data can be transferred to this virtual memory, freeing up RAM for other processes.

Virtualization

Virtualization is a technique employed by the OS to isolate each application, providing it with its own virtual machine that it operates under the assumption of having exclusive control. This isolation prevents applications from interfering with one another and allows the OS to maintain control over system resources. Each virtual machine possesses its own virtual memory, CPU, and additional resources, enabling the OS to manage each application independently.

In conclusion, the OS leverages a combination of process scheduling, memory management, and virtualization to effectively manage the execution of multiple applications. This strategy promotes efficient utilization of system resources and ensures that each application has the necessary resources to function correctly.