Centre tapped potentiometers

~S~ All,
Am looking into a source of potentiometers for my next project and have seen the term 'centre tapped' as an option.
I'm having difficulties getting my head around what this means - can anyone help me out?
What does 'centre tapped' mean and why might it be a useful thing to have?
All the best,
Pads
Am looking into a source of potentiometers for my next project and have seen the term 'centre tapped' as an option.
I'm having difficulties getting my head around what this means - can anyone help me out?
What does 'centre tapped' mean and why might it be a useful thing to have?
All the best,
Pads