# SHA256 on 1x A4

SHA256 is an abbreviation for: Secure Hash Algorithm 2^ 256 (SHA256).

SHA256 is the worlds tech industry standard for securing digital information on the internet.

2^ 256 is a mathematical sum: 2 x 2 x 2…etc reoccurring 256 times.

SHA256 is a cryptographic number (meaning it is non-numeric). Because it is non-numeric it has no mathematical formula & therefore no numeric label as it cannot be counted. This is because it starts with a line of zero’s (see image above).

In an attempt to illustrate its proportional size, 256 can be divided evenly by 8. Sum: 256 / 8 = 32. Therefore (2^ 32)^ 8 = 2^ 256.

2^ 32 (2 x 2 x 2…etc r32) = 4,294,967,296

4,294,967,296^ 8: 4,294,967,296 x 4,294,967,296 x 4,294,967,296 x 4,294,967,296 x 4,294,967,296 x 4,294,967,296 x 4,294,967,296 x 4,294,967,296 = 2^ 256 (an astronomically large number).

Because SHA256 is a cryptographic number & starts with a line of 0000’s it is non-numeric, meaning it cannot be calculated. This means there is no way to reverse calculate it, & so anything that has been hashed (scrambled) by SHA256 cannot be undone unless you have the answer in the form of its private key.

…there is no way of working out SHA 2²⁵⁶, so the ONLY way to get it is to guess. The number of guesses per second in relation to proof of work in Bitcoin is called the Hashrate.

SHA256 is used to generate economic competition within Bitcoin as Bitcoin mining operations compete to provide more Hashrate than one another in an attempt to win the Bitcoin block reward along with the block fee. The Hashrate difficulty adjustment is altered according to how much Hashrate the network has, which means SHA256 is found approximately every 10 minutes on average.

The block reward is the freshly minted/newly created Bitcoin that is programmed into the first bit of data that enters a new block.

The block fee is the accumulated total fees that are attached with each transaction contained in a block.

Mining operations compete to find SHA256 to win the block reward, but also compete to create an optimum size block to take advantage of the volume of transaction fees contained within it.