OS Internals

Operating System Internals: A Deep Dive An operating system is the software that coordinates hardware and programs. If you think of a computer as a factory, the OS is the manager that assigns tasks, handles memory, and talks to devices. This article looks inside the system to explain how core parts work together, in plain terms. At the heart is the kernel, a small, trusted program that runs in privileged mode. It validates actions, schedules work, and protects memory. User programs run with limited rights, and every request to the hardware passes through system calls or traps. ...

Inside the Core: Kernel and Drivers An operating system hides its complexity behind two main ideas: the kernel and the drivers. The kernel is the brain of the system. It decides who runs, when, and how memory and devices are used. Drivers are smaller helpers that talk to specific hardware, such as a keyboard, a disk, or a network card. Together, they keep your programs safe while letting the hardware do its work. ...

Modern Operating Systems Internals: Kernel and Beyond Modern operating systems act as a stable layer between applications and hardware. The kernel coordinates CPU time, memory, devices, and security to let apps run smoothly. This space is big, but you can understand it by focusing on a few core duties and how they connect. Key responsibilities of the kernel include: Process management: creating, terminating, and scheduling tasks Memory management: virtual memory, paging, and protection Interrupts and exceptions: responding to hardware events I/O and device drivers: talking to disks, keyboards, networks, and more File systems: organizing names, metadata, caching, and journaling Interprocess communication: pipes, signals, shared memory Concurrency and synchronization: locks and wakes Security and isolation: enforcing privileges and boundaries Kernel space is privileged code. Applications run in user space, and when they need services, they issue system calls. Those calls switch the processor into kernel mode, the kernel does the work, and the result is returned to user space. This separation keeps the system safe and reliable. ...