Cryptographic hash functions are primarily used in password security and encryption. They are the fundamental building blocks that are used in many cryptographic algorithms and protocols. Most commonly know are MD5 (message digest 5, the iteration after 4) and SHA-256. Bitcoin uses the hashcash-SHA-256^2 proof of work function developed by Adam Back. Originally proposed as a way to prevent spam e-mail and anonymous remailers.
Hash functions take an input of arbitrary size and uses a mathematical transformation to create a deterministic output, one that is always the same for a given input, called a digest or hash. The size of the output is going to be fixes in length. In bitcoin (SHA-256) the hash is going to be 256-bit in length.
There is a difference between cryptographic hash functions and traditional hash functions. Cryptographic implies the hash function conforms to a certain set of design goals which enable it…
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NEW YORK (CNNMoney) — Finally! The Nasdaq topped the 5,000 level Monday for the first time since March 2000.
The Nasdaq closed at 5,008. It is only the third time it has ever finished above 5,000. Believe it or not, the Nasdaq is now just 2.4% from the all-time peak of 5,132.52 it notched during the Dot-com bubble.
More records: Stock markets around the world have been crushing records lately. The Nasdaq, home to Apple, Microsoft, Google, Intel and many other prominent tech stocks, is actually the laggard. It’s the last major index to come close to its all-time highs.
The Dow and S&P 500 have been routinely hitting new records for the past year.
A lot of people have concerns that this might be a warning sign that stocks are back at lofty levels again, but much is different now versus the Dot-com era. Many of the companies leading…
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