What is Linux

What is Linux? #

Review

  1. 2019/08/03

Linux is a free and open-source operating system kernel that was first released by Linus Torvalds in 1991. It has since grown into a complete operating system ecosystem that powers everything from smartphones to supercomputers.

每一种操作系统都是在他专门的硬件架构上面运行的。Linux具有可移植性，可在多种设备上面运行。 Linux仅是内核与内核提供的工具，不过由于内核、内核工具与软件开发者提供的软件的整合，使得 Linux成为一个更完整、功能强大的操作系统。

History of Linux and Unix #

Early Unix Development #

  • 1969: Ken Thompson and Dennis Ritchie at Bell Labs developed the first version of Unix
  • 1973: Unix was rewritten in C, making it more portable and easier to maintain
  • 1977: Berkeley Software Distribution (BSD) was created at UC Berkeley
  • 1979: AT&T released System V, marking the beginning of commercial Unix

The Free Software Movement #

  • 1984: Richard Stallman launched the GNU Project to create a free Unix-like operating system
  • 1985: The Free Software Foundation (FSF) was established
  • 1989: The first version of the GNU General Public License (GPL) was released
  • 1991: Linus Torvalds released the first version of the Linux kernel

Key Components of Linux #

The Linux Kernel #

  • Core component that manages system resources
  • Handles hardware communication
  • Provides essential services to other software
  • Released under the GNU GPL license

GNU Tools and Utilities #

  • GNU C Compiler (GCC)
  • GNU Core Utilities
  • Bash shell
  • GNU C Library (glibc)
  • Emacs text editor

Linux Distributions #

A Linux distribution (distro) combines the Linux kernel with:

  • System software and libraries
  • Package management system
  • Desktop environment
  • Applications and tools

Popular distributions include:

  • Debian and its derivatives (Ubuntu, Linux Mint)
  • Red Hat Enterprise Linux and its derivatives (Fedora, CentOS)
  • Arch Linux
  • Gentoo
  • openSUSE

Linux Features and Advantages #

Technical Features #

  • Multi-user and multi-tasking capabilities
  • Strong security model
  • Extensive hardware support
  • High stability and reliability
  • Excellent networking capabilities

Advantages #

  • Free and open-source
  • Highly customizable
  • Strong community support
  • Excellent for development
  • Wide range of applications
  • Strong security features

Linux in Different Environments #

Desktop Computing #

  • User-friendly distributions with modern desktop environments
  • Office applications, web browsers, and multimedia tools
  • Gaming support through Steam and other platforms

Server Environments #

  • Web servers
  • Database servers
  • Cloud computing platforms
  • Enterprise applications

Embedded Systems #

  • Smartphones (Android)
  • IoT devices
  • Network equipment
  • Industrial control systems

Cloud and Virtualization #

  • Container technologies (Docker, Kubernetes)
  • Virtual machines
  • Cloud infrastructure
  • Serverless computing

Learning Linux #

GNU是GNU‘s Not UNIX 开源就是在软件发布时，将源代码一起公布。 自由软件的重点并不是“免费”，而是指具有“自由度（freedom）”的软件。用户可以自由地址行、复 制、在发行、学习、修改与强化自由软件。 但不能做：

  • 修改版权：GPL授权的自由软件，在自己修改代码后，不能取消GPL授权
  • 单纯销售：你不能单纯销售自由软件

Essential Skills #

  1. Basic command line operations
  2. File system navigation and management
  3. Text editing (vi/vim)
  4. Shell scripting
  5. Package management
  6. User and permission management
  7. Network configuration
  8. System administration basics

POSIX（Portable Operating System Interface）可移植操作系统接口，重点在于规范内核与应用程序之间的接口，由IEEE发布。

Linux，吉祥物企鹅 1991年，0.02版 1994年，1.0版 1996年，2.0版， 2011年，3.0版， 2015年，4.0版，

Linux发行版（Linux distribution）：内核+软件+工具+可完全安装程序 更严谨的Linux发行版本可以考虑使用Debian 性能至上考虑，可以选择Gentoo

嵌入式系统，理论上你应该不会修改到这个操作系统，故得此称。 虚拟化，指的是在一台物理主机上面模拟出多个逻辑上完全独立的硬件，这个假的虚拟出来的硬件主机，可以用来安装一台逻辑上完全独立的操作系统。

如何学习？ #

  • 网络基础与安全很重要，例如TCP/IP的基础知识，网络路由的相关概念等。
  • 计算机概论与硬件相关知识
  • Linux安装与命令
  • Linux操作系统的基础技能
  • VI文本编辑器
  • Shell与Shell脚本的学习
  • 软件管理
  • 有系统第设计文件目录，不要随便到处保存文件
  • 养成一个做记录的习惯，错误整理、总结
  • 好内容要留存
  • 开发者要让机器迁就人

Reference #