Hacking Linux password and securing Linux Password using Linux Grub security

Every Linus user whether  basic users or linux system admin they must face a problem regarding linux password.sometimes someone forget sometimes some other reasons.That's why in this tutorial we will learn how to hack linux password specially RHEL5 RHEL6 CentOS5 and CentOS6 and at the same time we will also learn to secure Linux Password using Linux Grub Security.This tutorial is also about Root user password Recovery in Linux. We will also learn what to do when you forget your Linux Root password.We will see method to break or bypass Linux Password at Boot Time.