To find the version of the Linux kernel (the core of the operating system) on your system, you can use the uname command with the -r flag. This will print the current version of the kernel, along with any additional information such as the patch level or build date.
For example:
$ uname -r 5.4.0-62-generic
Alternatively, you can also use the /proc/version file to display the kernel version. This file contains information about the kernel, including its version and other details such as the build date and compiler used. To display the contents of this file, you can use the cat command:
$ cat /proc/version Linux version 5.4.0-62-generic (buildd@lcy01-amd64-004) (gcc version 9.3.0 (Ubuntu 9.3.0-10ubuntu2)) #69~20.04.1-Ubuntu SMP Mon Nov 23 17:08:35 UTC 2020
Note that the kernel version may not always be the same as the version of the operating system or distribution. Some distributions, such as CentOS and Red Hat Enterprise Linux, use a custom kernel that is based on the upstream Linux kernel but includes additional patches and features. In these cases, the kernel version may be different from the version of the operating system.