In order to use encryption and decryption in PHP, we need to inatall PHP extension mcrypt.

These days most websites uses Cloudflare for there protecting against DOS or DDOS attacks. Cloudflare is free and easy to setup. Cloudflare conceals the IP address of the website in order to protect it from attack.

7zip is a free file archiving and file compression / decompression utility. 7zip is a free open source better alternative to both WinRAR and WinZip. It currently support over 45 formats.

/bin/bash^M: bad interpreter: No such file or directory is a error thrown by Linux and Mac OSX operating systems when a Shell script is executed which was created in Windows environment.

Raspberry Pi, Tails, Android and other Linux OS sometimes create partition on SD Cards and USB devices. When these devices plug in to a laptop or a PC they show only part of the storage capacity of USB or SD card.