Chirality

Chirality n. (Kie-ral'-it-ee) The state or quality of being chiral, almost always in reference to molecules.

Basically, chirality is when a three dimensional structure's mirror image is structurally different than the original.
While refering to molecules, it is important to note that molecules can twist and rotate freely at certain points in their structure, which increases the range of what may be considered structurally equivalent.

Water lacks chirality. Even though sucrose is often shown in structural diagrams with the OH groups all on one side, the natural twisting and turning that occurs makes the mirror image equivalent.

Thalidomide is chiral. This is because, like all ethers and other ether-contaning molecules, it has a double bond (only single covalent bonds rotate freely) in its 'middle'. Both structurally differing forms are generated during the manufacture of thalidomide. While one form is fairly benign to humans when taken in controlled doses, it's mirror image is very harmful to the developmental processes of fetuses. (cf. children of thalidomide)
There is currently no clear or simple way of seperating one version from the other.

Apperently, 'Chirality' is also the name of a manga that Satoshi Urushihara is known for working on.
Additionally, 'Chirality' is not an polished, addictive Pipe Dream/Tetris-type game for the Macintosh put out by Ambrosia Software - you're thinking of 'Chiral'.

Certain points in the above writeup should be clarified.

• Sugar is chiral.
• No matter how much a molecule rotates or twists, it CANNOT change its chiral form.
• Ethers do not have double bonds.
• Double bond have cis/trans stereochemistry, not chirality.
• Thalidomide is not an ether. It is C1(=O)c2ccccc2C(=O)N1[C3@H]C(=O)NC(=O)CC3, in fact.

The truth of the second point will become clear if you lift up your typing appendages from the keyboard and try wiggling them until they match. Unless you are a fourth dimensional being this will not be possible.

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another noder msged me to explain in detail why H-Monk may be right in certain ways - let me be clear I DO NOT CARE! If he is suggesting that rotation alone can alter chirality of molecules then he is wrong. However, I think he was referring to anomerism - a property of sugars that does make them interchangeably chiral. So α-D-glucopyranose can become β-D-glucopyranose via the linear molecule - BUT this requires a reaction to take place (cyclisation by internal re-arrangement of atoms) so that it is not strictly the same molecule.

I'd like to point out that chemists don't have a monopoly on studying objects with intrinsic chirality, or handedness.

In the standard model of elementary particle physics, only left-handed particles and right-handed anti-particles interact via the weak interactions. Thus, it is a chiral theory.

T.D. Lee and C.N. Yang won the Nobel Prize in 1957 for predicting that the weak interactions were chiral, i.e. violated parity. C.S. Wu and collaborators later verified their prediction experimentally by looking at radioactive decay of a cobalt isotope. Of course now it is extremely well verified in high energy experiments.