Linux Operating System Fundamentals

Study Notes

Linux is an open-source Unix-like operating system kernel, forming the basis of numerous distributions referred to as Linux distributions or distros.
It is built on principles of collaboration, flexibility, and freedom, enabling users to customize and configure their systems to meet specific needs.

Linux features a command-line interface (CLI), offering powerful tools for system administration and scripting.
It has a multi-user capability, ensuring concurrent access by multiple users, with robust security features including file permissions and user authentication.
Linux supports a wide range of file systems, networking protocols, and hardware platforms, making it versatile for various applications.

Linux is renowned for its stability and reliability, attributed to its modular design and robust architecture.
It continues to thrive as a leading choice for both personal and enterprise computing due to a vast community of developers and enthusiasts contributing to its development and support.

Fundamental concepts of Linux include filesystem hierarchy, package management, and process management.
Understanding these concepts is essential for harnessing its full potential and maximizing efficiency in system administration and development tasks.

cd: Change directory, used to navigate between different directories in the file system.
ls: List directory contents, displays the files and directories in the current directory.
pwd: Print working directory, shows the current directory you are in.
mkdir: Make directory, creates a new directory.
rmdir: Remove directory, deletes an empty directory.
rm: Remove, deletes files and directories.
cp: Copy, copies files or directories from one location to another.
mv: Move, moves files or directories from one location to another, also used for renaming files.
touch: Creates an empty file or updates the access and modification times of a file.
cat: Concatenate and display files, displays the contents of a file.
grep: Global regular expression print, searches for a pattern in files and prints matching lines.
chmod: Change mode, changes the permissions of a file or directory.
chown: Change owner, changes the owner of a file or directory.
sudo: Superuser do, allows users to perform tasks with superuser (root) privileges.
df: Disk free, displays information about disk space usage.
du: Disk usage, shows the disk space used by files and directories.
ps: Process status, displays information about active processes.
kill: Terminates processes by process ID.
top: Displays system resource usage and running processes.
tar: Tape archive, used to archive files and directories into a single file.