Linux Background knowledge

Linux development history

1. In 1991, Linus Torwalds released the Linux0.02 version, capable of running GCC and bash
2. 1994, Linux1.0 version released

Linux and Open source program

1. There is an online Richard Stallman in the CAs speech, the following concepts are very clear (really admire the explanation of foreigners, very easy to understand), you can search.

2. You can also refer to this blog post why the GPL is a better open source license

3. GNU (GNU is not Unix), a public program launched in 1983 by Richard Stallman (the main sponsor and spiritual leader of free software), was designed to create a completely free operating system called GNU. The sign is the African wildebeest. Richard worked at MIT's AI lab, when many hackers in the lab stopped developing free software and used the software for commercial purposes, which made the RS very uncomfortable and launched the campaign.

   The GPL (GNU General public License) is the GNU Universal Common License, the concept of anti-Copyright (Copyleft). The software of the gun follows this protocol more. The GPL guarantees that open source software can continue to be published and disseminated. There is also a relatively loose LGPL protocol. You only need to make the modified part open source, so it's more for commercial use. In fact, the first L in this LGPL was originally referring to the library rather than the lesser.

   FSF (Free software fodation) is a foundation created by Richard Stallman in order to achieve his GNU ideals.

   Gnu/linux both should be project-supported, picking, which is now in harmony. GNU needs an operating system kernel, Linux running a lot of free software, such as gcc,gedit,notepad,mysql,firefox,php.

Linux Hardware knowledge

1. The hard disk interface refers to the connection between the hard disk cache and main memory, and we commonly use three kinds of IDE, SATA and SCSI. IDE old-fashioned interface, very wide many lines of the kind, basically has been eliminated SATA now commonly used hard disk interface Scsi/sas with the hard disk interface commonly used in the server, SAS is a new generation of SCSI technology, compatible with SCSI

2. Two IDE drives (Master & slaver), four physical hard drives per IDE interface

3. Up to 16 drives per SATA interface

Linux file directory

1. Files used during boot/boot system startup
2. /usr system where the software is stored
3. /Home User House Directory
4. /var/log Log
5. /tmp temp file
6. /dev Device files
7. /opt Optional Software
8. /sbin Standard system Management files
9. /bin Standard System Utility
10. /etc configuration file
11. /lin Program Library

Linux Background knowledge