When something possesses the quality of chirality it means that has an orientation or a handedness. This 'Handedness' can be looked upon as a spin direction or Angular direction. In the northern hemisphere an atmospheric high pressure zone has clockwise chirality and in the southern hemisphere high pressure zones are preferentially anti-clockwise. It also manifests itself in people as a preference for a hand or foot, Thus to be 'right handed' is to have right handed chirality. There are as far as I know only two types of chirality ie: left and right however this does not preclude the possibility for a third or fourth type of chiral behaviour. This would in effect require the inclusion of extra dimensions.

The Fovea is the centre of vision, the area which we use to focus on an image. It consists of densly packed retinal cells called cones which are responsive to coloured light.