All of these technologies of Bitcoin were available before the development of its development; it is to Satoshi to put all of them together to get the secure, reliable network known as Bitcoin

Block Chain - There are many blockchains, and bitcoin isn't the first blockchain to ever be made. Describing Bitcoin as just blockchain technology would be like relating a motor vehicle to the technology of transmissions. Although it is a vital part of Bitcoin, it is not the only technology bitcoin uses.

Block Chains are digital ledgers used to record things like transactions or perhaps moves in a game of chess. Bitcoins blockchain creates a new __immutable__ block of transactions every 10 minutes.

Cryptography -

Cryptography is a method of protecting information and communications through the use of codes, so that only those for whom the information is intended can read and process it.

In computer science, cryptography refers to secure information and communication techniques derived from mathematical concepts and a set of rule-based calculations called algorithms, to transform messages in ways that are hard to decipher. These deterministic algorithms are used for cryptographic key generation, digital signing, verification to protect data privacy, web browsing on the internet and confidential communications such as credit card transactions and email.

Hashing -

Hash functions are any function used to map data of arbitrary size to fixed-size values. The values returned by a hash function are hash values, hash codes, digests, or simply hashes. The values are generally used to index a fixed-size table called a hash table.

Hashing consists of converting a general string of information into an intricate piece of data. Hashing's purpose is to scramble the data so that it completely transforms the original value, making the hashed value different from the original.

Hashing uses a hash function to convert standard date into an unrecognizable format. These hash functions are a set of mathematical calculations that transform the original information into its hashed values, known as the hash digest or digest in general. The digest size is always the same for a particular hash function like MD5 or SHA1, regardless of size.

SHA 256 -

SHA stands for Secure Hash Algorithm; the 256 is the final hash digest value, i.e., regardless of the size of plaintext/cleartext, the hash will always be 256 bits. SHA 256 was published in 2001 as a joint effort between NIST and NSA to introduce a successor to the SHA 1 family of algorithms. SHA 1 needed to be replaced as it was losing strength to brute force attacks. A brute force attack would be like someone repeatedly guessing your password till they were successful.