What is the t in drwxrwxrwt or the value of t? [duplicate]

ls -al / shows a folder:

drwxrwxrwt 2 root root 4096 Feb 26 09:00 tmp

What does the last character t mean in drwxrwxrwt?


This is the sticky bit, see this page : http://en.wikipedia.org/wiki/Sticky_bit