Question

I need a resume of all the important commands of linux with their operation

Answer 1

ls [option(s)] [file(s)]

ls command is used to list the files in the folder with hidden and full listing detailed view.

-l detailed list
-a displays hidden files

cp [option(s)] sourcefile targetfile

Copies sourcefile to targetfile.

-i Waits for confirmation, if necessary, before an existing targetfile is overwritten
-r Copies recursively (includes subdirectories)

there are too many switches but its not listed here.

mv [option(s)] sourcefile targetfile

Copies sourcefile to targetfile then deletes the original sourcefile.
-b Creates a backup copy of the sourcefile before moving
-i Waits for confirmation, if necessary, before an existing targetfile is overwritten

rm [option(s)] file(s)

Removes the specified files from the file system. Directories are not removed by rm unless the option -r is used.

-r Deletes any existing subdirectories
-i Waits for confirmation before deleting each file.

cd [directory]
change directory

mkdir [option(s)] directoryname
make directory with -p parent directory and subdirectory creating

rmdir [option(s)] directoryname
remove directory

chown [option(s)] username.group file(s)
change ownership of file or folder

chgrp [option(s)] groupname file(s)
change group of the user

chmod [options] mode file(s)
change file mode with read write execution rights can be change by the command.

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