The larynx is a 5cm long tube that separates the oesophagus(the pipe that goes from the mouth to the stomach) from the windpipe(trachea). It is found in the neck at the level of the 'Adam's apple', which is often much easier to notice in men than it is in women. It is an air passage that extends from your tongue to your trachea and helps produce the sounds you make when you speak. It also stops food entering your trachea and allows you to breathe.
Attribution: BUPA