Useful Linux Commands

10 Useful Linux Commands

Simply put, the command line is powerful; an army of tools exist that can take what would be a tedious job in a graphical program and turn it into a task that takes just a few seconds. Removing the last four lines in every row of a large file would be a lengthy process in a graphical application, but can become trivial and automated on the command line.

Flexibility aside, it's also important to note that some Linux systems lack a graphical interface at all and that some systems may become damaged in such a way as to make it impossible to bring up anything other than the command prompt. In these cases it's important to be able to navigate on the command line with enough proficiency to perform whatever tasks need to be done from backing up some files to disabling a dying piece of hardware.

The commands used at the command line may seem a little cryptic due to their tendency to be very short. This is because the roots of the Linux command line are from systems where a single letter entry could take a significant amount of time to travel from a terminal, to a central server and back to the terminal where it was printed onto a roll of paper. In those old systems, the shorter the input was, the better, as it meant less time waiting to issue your command and receive output. The best thing you can do to remember what commands stand for is to find out what word the command is an abbreviation for. This can go a long way to remembering the command later.

1. Command is LS

The command “ls” stands for (List Directory Contents), List the contents of the folder, be it file or folder, from which it runs.

Command “ls -a“, list the content of folder, including hidden files starting with ‘.’.

2. Command is LSBLK

The “lsblk” stands for (List Block Devices), print block devices by their assigned name (but not RAM) on the standard output in a tree-like fashion.

Note: lsblk is very useful and easiest way to know the name of New Usb Device you just plugged in, especially when you have to deal with disk/blocks in terminal.

3. Command is MD5SUM

The “md5sum” stands for (Compute and Check MD5 Message Digest), md5 checksum (commonly called hash) is used to match or verify integrity of files that may have changed as a result of a faulty file transfer, a disk error or non-malicious interference.

4. Command UNAME

The “uname” command stands for (Unix Name), print detailed information about the machine name, Operating System and Kernel.

5. Command HISTORY

The “history” command stands for History (Event) Record, it prints the history of long list of executed commands in terminal.

6. Command SUDO

The “sudo” (super user do) command allows a permitted user to execute a command as the superuser or another user, as specified by the security policy in the sudoers list.

7. Command MKDIR

The “mkdir” (Make directory) command create a new directory with name path. However is the directory already exists, it will return an error message “cannot create folder, folder already exists”.

8. Command TOUCH

The “touch” command stands for (Update the access and modification times of each FILE to the current time). touch command creates the file, only if it doesn’t exist. If the file already exists it will update the timestamp and not the contents of the file.

9. Command CHMOD

The Linux “chmod” command stands for (change file mode bits). chmod changes the file mode (permission) of each given file, folder, script, etc.. according to mode asked for.

There exist 3 types of permission on a file (folder or anything but to keep things simple we will be using file).

10. Command CP

The “copy” stands for (Copy), it copies a file from one location to another location.

There are more useful commands to implement in Linux enviroment. This are some 10 basic day to day commands.

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