how to go into single user mode in ubuntu

Single User Mode

Single User Mode (also known as Maintenance Mode) is a mode in Unix-like operating systems such as Linux OS, where we can perform any command with the root privilege, Ex change root password, recover permission etc.

Enter into Single User Mode

• Reboot the machine and press ESC button.
• you will be see ubuntu edit mode.

• press e button for enter into single user mode.
• you will be see like below picture. 

• go to end of the line of linux.
• edit the line with give space and write 1  
• and now press Ctrl+x for boot into single user mode.
• also see in below picture.

• after that press enter for the maintenance mode.

• Now you can run all command's
• and also change root password and change permission.

• After run command
• out from the maintenance mode { write the word exit } 
• now you will be access normal mode.