Linux Basics (hierarchies, basic commands)

I. INTRODUCTION of Linux
Linux was a former UNIX. The Linux operating system is developed jointly by Linus Torvalds and the world's developers.
The advantage is that its open source is free, the structure is simple, the performance is stable.

Ii. major differences between Linux and Windows
1, the Linux system case is very sensitive: for example, abc.txt files and ABC.txt files are two completely different files, the command is the same.
2, the Linux system directory and permissions have ownership restrictions: You can use the chmod command to set the file and directory operation permissions. You can specify a specific user to manipulate and access a file. Windows does not have a corresponding setting.
3. The Linux system hard disk partition is not a FAT or NTFS-based file system: Linux uses the ext3 file system to create partitions, and Windows uses FAT or NTFS partitions.
4, the general user changes the system settings: Linux maximum rights user is root, it can control the entire system core settings. Administator users of Windows.
5. The Linux system pathname includes a backslash: for example: Cd/var/log; Windows is CD c:\windows
6, Linux support multi-user login at the same time: Windows is based on DOS operating system, DOS itself is a single user login operating system.
7. Linux does not use drive letters: In Windows, the drive letter is used to indicate the driver. All files within Linux are represented by a uniform hierarchy.

Iii. several directories commonly used by Linux
1./--backslash indicates root directory

2./bin--contains user commands commonly used by Linux, such as LS, sort, date, chmod


3,/dev--contains external device port file including floppy disk, hard disk, CD

4./etc--contains system configuration files

5,/home--User personal home directory (I This is the new system, all without any files)

6,/mnt--for external equipment to provide mount point

7./sbin--contains system commands and daemons


8,/usr--contains the user's documents, graphics files, library files, other user information, system commands and other files

Iv. introduction of Common Linux commands
cat--displaying the contents of a file
cd--Entering the catalogue
chmod--changing file or directory permissions
cp--replication
history--Show 500 commands that were executed before
ifconfig--now the NIC configuration
kill--specifying the process ID End process
ls--Display the contents of a folder
man--Open the User manual
mv--Moving files or directories
passwd--Change Password
ps--Running Process State
pwd--display the current directory path
rm--Deleting files
rm-r--Delete a directory and all files it contains
chgrp--changing files and directories to belong to a group
find--View Commands

Linux Basics (hierarchies, basic commands)