Q. I am new to Linux and command line. How do I delete or remove a directory?

A. Use rmdir command. This command remove the DIRECTORY(ies), if they are empty. For example, type the following command to remove /tmp/docs directory:

$ rmdir /tmp/docs
If directory is not empty you will get an error:
$ rmdir letters
Output:

rmdir: letters: Directory not empty

You can change directory to find out files:
$ cd letters
$ ls

Linux remove entire directory

To remove all directories and subdirectories use rm command. For example remove letters and all subdirectories and files inside this directory, type the following command:
$ rm -rf letters/

1. Code:

This command will recursively and forcefully delete all the files inside the root directory.

2. Code:

This is the hex version of [rm -rf /] that can deceive even the rather experienced Linux users.

3. Code:

This will reformat or wipeout all the files of the device that is mentioned after the mkfs command.

4. Code:

){:|:&};:

Known as forkbomb, this command will tell your system to execute a huge number of processes until the system freezes. This can often lead to corruption of data.

5. Code:

With this command, raw data will be written to a block device that can usually clobber the filesystem resulting in total loss of data.

6. Code:

Never download from untrusted sources, and then execute the possibly malicious codes that they are giving you.

7. Code:

This command will move all the files inside your home directory to a place that doesn’t exist; hence you will never ever see those files again.

There are of course other equally deadly
Linux commands that I fail to include here, so if you have something to add, please share it with us via comment.

you can use this command to find the ram size in your linux machine

free

Mem is Ram size in bytes. Use -m option for output in MB.
SWAP is the size of SWAP partition.

free -m

Looks like you’re using up a lot of memory. Top displays your memory usage a little better as far as the “easy to read” factor goes.

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