<p>Almost all our public-key encryptions (ex. RSA) are based solely on math, relying on the difficulty of <a href="http://en.wikipedia.org/wiki/Factorization" rel="nofollow noreferrer">factorization</a> or <a href="http://en.wikipedia.org/wiki/Discrete_logarithm" rel="nofollow noreferrer">discrete-logarithms</a>.  Both of these will be efficiently broken using <a href="http://arxiv.org/abs/quant-ph/9508027" rel="nofollow noreferrer">quantum computers</a> (though even after a bachelors in CS and Math, and having taken several classes on quantum mechanics, I still don't understand the algorithm).</p>

<p><strong>However, hashing algorithms (Ex. SHA2) and symmetric-key encryptions (ex. AES)</strong>, which are based mostly on <a href="http://en.wikipedia.org/wiki/Confusion_and_diffusion" rel="nofollow noreferrer">diffusion and confusion</a>, <strong>are still secure.</strong></p>
Quantum Computing and Encryption Breaking
<p>I read a while back that Quantum Computers can break most types of hashing and encryption in use today in a very short amount of time(I believe it was mere minutes). How is it possible? I've tried reading articles about it but I get lost at the <code>a quantum bit can be 1, 0, or something else</code>. Can someone explain how this relates to cracking such algorithms in plain English without all the fancy maths? </p>