The Basics of Linux
Unlike proprietary software, which is sold under exclusive licenses, linux is open source and free to use for anyone. Its flexibility and security model have made it a common choice for enterprise applications and embedded systems. It is considered high-performing, stable and efficient and has the support of a worldwide community. It powers all kinds of technology, from retail point-of-sale systems to the world’s most powerful supercomputers.
The Linux kernel enables an operating system to manage low-level activities such as memory and CPU management, hardware access, and input/output. It also serves as an abstraction layer between user space and the hardware, enabling users to perform system tasks without being aware of the underlying hardware or software. The kernel manages these functions by using libraries that turn specific functionality on and off. This makes it possible for a programmer to customize the kernel to meet their specific needs.
A key component of the Linux kernel is the init system, which starts daemons or services that manage system processes. The original Linux init system, sysvinit, used scripts in the /etc/init.d directory to start, stop, and restart services in a sequential order based on the system runlevel. More modern Linux init systems include systemd, Upstart, and OpenRC. These init programs are responsible for coordinating the various sub-systems that control a computer, such as user space and the desktop environment.
In addition to these core components, Linux has a rich and growing library of software and applications that users can install. These range from desktop tools and programming languages to multiuser business suites. Most Linux distributions offer a central database to search for and download additional applications.
Almost anything that can be created on a PC can be run on Linux, making it an excellent choice for developers and IT professionals looking to test new technologies. It is also ideal for running pilot projects and prototyping because of its flexible development model, low cost, and efficiency.
Linux is widely viewed as secure, especially when configured with SELinux, which has been part of the Linux kernel since 2003. SELinux allows administrators to monitor, control and limit application access and permissions within the OS.
The Linux kernel communicates with external hardware devices through drivers, which are software that enable the operating system to send requests to a device for information or commands. This is important for managing communication between a system and its peripheral hardware, such as USBs, graphics cards, sound cards, and network adapters.
Despite being considered an expert-level OS, Linux is easy for beginners to learn and use. Its modular design means that programmers can audit code, fix bugs, and add new functionality quickly. Likewise, its layered security model prevents hackers from exploiting vulnerabilities in a single component of the OS. Additionally, it’s a very versatile OS that can adapt to virtually any hardware or software requirement. This versatility has led to Linux powering all kinds of technology, from small, data-gathering edge devices to large, cloud-native applications.
