Kernel
The kernel is the core component of an Operating System that has direct control over hardware resources — CPU, memory, and devices — and mediates access to them for all other software running on the machine.
17 resources across 3 libraries
Glossary Terms(5)
Operating System
An operating system (OS) is the foundational software layer that manages a computer's hardware resources and provides common services to application programs,…
Kernel
The kernel is the core component of an Operating System that has direct control over hardware resources — CPU, memory, and devices — and mediates access to the…
Process Scheduling
Process scheduling is the operating system mechanism that decides which of the many runnable processes or threads gets access to the CPU at any given moment, a…
Virtual Memory
Virtual memory is an operating system technique that gives each process the illusion of a large, contiguous, private address space, while the Kernel transparen…
File System
A file system is the method and data structure an Operating System uses to organize, name, store, and retrieve data on persistent storage devices such as hard…
Study Notes(2)
Interview Questions(10)
What is a System Call?
A system call is the controlled interface a user-space program uses to request a privileged service from the operating system kernel, such as reading a file, a…
What is an Interrupt?
An interrupt is a signal to the CPU, generated by hardware or software, that forces the processor to pause its current instruction stream and immediately trans…
Containers vs VMs: How Do They Differ at the OS Level?
A VM virtualizes hardware and runs a full separate guest kernel on top of a hypervisor, while a container shares the single host kernel and is isolated only by…
What are Linux Namespaces and OS-Level Virtualization?
Linux namespaces are a kernel feature that partitions a single global resource — process IDs, network interfaces, mounts, hostnames, users, and more — into iso…
What is a chroot Jail and What Are Its Limitations?
A chroot jail is created by the chroot() system call, which changes a process’s apparent root directory `/` to a chosen subdirectory, so the process — and anyt…
What is Linux Capability Dropping and Why Does It Matter?
Linux capabilities split the traditionally all-or-nothing power of the root user into dozens of independent, fine-grained privileges — like CAP_NET_BIND_SERVIC…
What is a File Descriptor Table?
A file descriptor table is a per-process array maintained by the kernel that maps small integers (file descriptors), which a process uses in system calls, to e…
What is the Open File Table?
The open file table is a kernel-wide (system-wide) structure of entries, each tracking the current file offset, access mode, and status flags for one open() ca…
What is the Buffer Cache in an Operating System?
The buffer cache is a region of kernel memory that holds recently used raw disk blocks so that repeated reads and writes to the same block hit fast RAM instead…
Page Cache vs Buffer Cache: What Is the Difference?
The page cache caches file contents in memory indexed by file and byte offset (used for regular file reads, writes, and mmap()), while the buffer cache histori…