Linux operating system basics, linux operating system

Linux operating system basics, linux operating system

Basic Principles of Linux:

1. It is composed of a single small program with a single purpose; it is combined to complete complex tasks;

2. Everything is a file;

3. Avoid capturing user interfaces as much as possible; (Avoid interacting with users as much as possible)

4. Save the configuration file in plain text format.

 

Shell: Human-Computer Interaction Interface

GUI interface: GUI interface

X-Window

Gnome: C

KDE: C ++

XFace

CLI interface: command line interface

Command prompt, prompt, bash (shell)

#: Administrator, root

$: Common User

Bsh

Bash

Csh

Zsh

Ksh

Tcsh

 

Command Format:

Command Option Parameters

Option:

Short options:-a. Multiple options can be combined. spaces are required between multiple options.

Long option: -- word

Parameter: target object of the command

Credential:

 

Virtual terminal (terminal): 6 virtual terminals, Ctrl + Alt + F1-F6

 

Command: startx & enter graphical interface

 

Linux users: root, student, visitor

 

Command su: switch user -- switch user

# Su-l user name -- full switch

Su user name-semi-Switch

# Passwd -- Change Password

Password Complexity rules:

1. Use at least three of the four category characters;

2. Long enough, greater than 7 digits;

3. Use a random string;

4. Regular replacement;

5. The cycle is large enough.