Linux utc,cst time and modification time

1. When installing Linux, there is an option to set the time:

System clock uses UTC, what does this UTC mean?

World Coordination Time (Universal times COORDINATED,UTC)
There are two kinds of time difference in GPS system, one is UTC, the other is LT (local time) is different from time zone, UTC is the time of 0 time zone, local time, such as Beijing Eight (East eight), UTC time is 0 points, time is eight hours later than in Beijing, in order to calculate

2, in Linux, with the DA

When Ta looks at time, it shows:
Wednesday, December 17, 2008 09:04:14 CST
What does this CST mean?

CST China Standard Time utc+8:00 Chinese coastal times (Beijing time)

3. Modify the system time

We generally use the "date-s" command to modify the system time. For example, the command to set the system time to July 26, 2005 is as follows.
　　
#date-S 07/26/2005
　　
The command to set the system time to 11:12 P.M. 0 seconds is as follows.
　　
#date-S 11:12:00

When the system starts, the Linux operating system reads the time from the CMOS into the system time variable, and the later modification time is realized by modifying the system time. To keep the system time consistent with the CMOS time, Linux writes the system time to CMOS at every time. Since this synchronization takes place at intervals (about 11 minutes), if the machine is re-started immediately after we execute the DATE-S, the modification time may not be written to the CMOS, which is the cause of the problem. You can execute the following command if you want to make sure that the changes take effect.
　　
#clock-W

Transferred from: http://hanzhantao.blog.163.com/blog/static/495975452009102462022868/

Linux utc,cst time and modification time