To make it easier to manage users, linux provides some common commands that allow you to add, delete, and modify users in a more standardized way.

To make it easier to manage groups, linux provides some common commands that allow you to add, delete, and modify groups in a more standardized way.

In order to make it easier to manage user and group permissions on files and directories, linux provides some common commands that can assign and reclaim permissions to users and groups in a more standardized way.

We can determine the permissions of a file by looking at the mode bits of that file.

The Linux core toolset provides us with some commands to view user-related information.

By compressing files and directories into a compressed file, we can easily move and back up the compressed file.

There are many things we can do with some combination of find and other commands. We can use some commands on the files we find.

Linux provides us with tools that make it easy for us to find the location of files and commands quickly and efficiently.

In linux, each running program will create at least one process in memory, and each process will be assigned a process ID, we can use the ID of the process to do the corresponding operation of a running program.

By using the nano text editor provided by Linux, we can easily do some simple text editing operations such as adding, deleting, modifying, etc.

Linux provides commands that allow you to view system-related information, and with these commands, you can quickly get some necessary system information.

Linux provides commands that allow you to view system’s date information, and with these commands, you can quickly get the date related information.

Linux provides commands that allow you to view system’s time information, and with these commands, you can quickly get the time related information.

Linux provides a printf command through which we can format what we want to output.

Bash’s startup configuration file can help us pre-load some other script files as well as preset general and necessary variables.

Bash provides two types of startup files, one that is loaded on login and the other that is loaded on non-login.

Linux provides us with some expansions for command, arithmetic, addition and subtraction, comparison, ternary, assignment, and process substitution operations.

Linux provides us with some expansions for duplicate, print current user’s directory, and parameter operations.

I believe that people who have learned how to program know what variables are, and at first it can be understood as an alias that points to the data stored in memory.

We can use the control operators provided by linux to facilitate the use of commands and the processing of the results of command execution.

We can use the tr command provided by linux to replace or remove text contents.