How can I create a directory and change my working directory to the new directory?

view story

http://askubuntu.com – I'm seeking a way to create directory and change my present working directory to newly created directory just by using a single command. How can I do this? i.e Instead of doing user@Computer:~$ mkdir NewDirectory user@Computer:~$ cd NewDirectory user@Computer:~/NewDirectory$ I want to do user@computer:~$ **command** NewDirectory user@Computer:~/NewDirectory$ What can the command be? (HowTos)