What is Cryptography?
Let's find out Cryptography meaning, definition in crypto, what is Cryptography, and all other detailed facts.
The prefix “crypt” means “hidden” and the suffix “graphy” means “writing”.
Back in the day, cryptography mainly dealt with the method of ciphers. Ciphers are the algorithms utilized to convert regular messages or “plaintexts” into ostensible gibberish or “ciphertext”. Moreover, the messages could be sent as letters, the receiver would then use the key to decrypt the ciphertext back into readable plaintext.
Without the knowledge of the key, the information conveyed in this manner was meaningless to any third-party adversary, even if the letter was physically received. That is, until the invention of cryptanalysis, the field that works with decoding encryption methods.
The first forms of ciphers, known as substitution and transposition ciphers and referred to collectively as classical ciphers, could be encrypted and decrypted manually. This meant that, at that time, they did not obscure the data sufficiently to withstand the cryptanalysis tools.
Three types of cryptography:
- Symmetric key cryptography - a sender and receiver of a message employ a single common key to encrypt and decrypt the message.
- Asymmetric key cryptography - a pair of keys is utilized to decrypt or encrypt data.
- Hash functions - no need for any key. A hash value with a defined length is computed based on the plain text, making it difficult to reconstruct the plain text's contents.
The rise of radio and internet communications resulted in the requirement for strong encryption since messages are now broadcasted promiscuously and could be hijacked at will.
A simple example of how hash functions work is to <strong>add up the digits of a multi-digit number until a single-digit output is reached<\/strong>. If the input is 173, adding up 1, 7, and 3 is <strong>11<\/strong>. The sum of adding 1 and 1 is 2, which is the final output. The output <strong>always has to be a<\/strong> single-digit, no matter how long the input number is digits-wise.<\/p>\n<p>Hash functions have several typical characteristics:<\/p>\n<ul>\n<li>Calculating the output for any given input has to be easy. However, it must be <strong>nearly impossible to reverse the process<\/strong>;<\/li>\n<li>Determinism – if a specific input is given to the algorithm, the same output must always be produced;<\/li>\n<li>Collision resistance – it should be very unlikely for two different inputs to produce an identical output;<\/li>\n<li>Avalanche effect – changing a single bit of the input data should create a completely different output.<\/li>\n<\/ul>\n<p>Hash functions can be utilized for various situations, like randomizing functions. They can also be <strong>applied as checksums for the integrity verification of computer files<\/strong> after their transmission of prolonged storage.<\/p>\n<p>Hash functions serve a vital role in <a href=https://www.bitdegree.org/"//crypto//learn//crypto-terms//what-is-mining/">cryptocurrency mining<\/strong><\/a> via the <a href=https://www.bitdegree.org/"//crypto//learn//crypto-terms//what-is-proof-of-work-pow/">Proof of Work (PoW)<\/strong><\/a> consensus algorithm. <a href=https://www.bitdegree.org/"https:////www.bitdegree.org//crypto//buy-bitcoin-btc/">Bitcoin (BTC)<\/strong><\/a>, one of the PoW-mined cryptocurrencies, relies on the <a href=https://www.bitdegree.org/"//crypto//learn//crypto-terms//what-is-sha-256/">SHA-256 <strong>hash function<\/strong><\/strong><\/a>. Miners working on adding a new <a href=https://www.bitdegree.org/"//crypto//learn//crypto-terms//what-is-block/">block to the chain need to produce a target – a hash value below a specific threshold. A successful outcome yields them rewards.<\/p>\n<p>Hashes are <strong>pseudorandom<\/strong>, meaning that they are deterministic. It is impossible to predict the output of an input of any value before it has been run through the hash function. This mechanic means that miners cannot generate new Bitcoin blocks randomly and their <strong>proof of work must be verified<\/strong>.<\/p>","definition":"an algorithm that produces fixed-size hash values from variable-size transaction inputs.","status":"published","meta_title":"What is Cryptographic Hash Function? Definition & Meaning | Crypto Wiki","meta_description":"Cryptographic Hash Function meaning: Cryptographic Hash Function - an algorithm that produces fixed-size hash values from variable-size transaction inputs.","meta_keywords":null}" :model="{"id":218,"wikipedia_url":"https:\/\/en.wikipedia.org\/wiki\/Cryptography","level":"easy","author_id":1,"created_at":"2023-06-19T06:58:59.000000Z","updated_at":"2024-01-07T08:15:09.000000Z","slug":"what-is-cryptography","title":"What is Cryptography?","section":"C","keyword":"Cryptography","content":"<p>The prefix “crypt” means “hidden” and the suffix “graphy” means “writing”.<\/p>\n<p>Back in the day, cryptography mainly dealt with the method of <strong>ciphers.<\/strong> Ciphers are the algorithms utilized to convert regular messages or <strong>“plaintexts”<\/strong> into ostensible gibberish or <strong>“ciphertext”.<\/strong> Moreover, the messages could be sent as letters, the receiver would then use the key to decrypt the ciphertext back into readable plaintext. <\/p>\n<p>Without the knowledge of the key, the information conveyed in this manner was meaningless to any third-party adversary, even if the letter was physically received. That is, until the invention of cryptanalysis, the field that works with decoding encryption methods.<\/p>\n<p><strong>The first forms of ciphers, known as substitution and transposition ciphers<\/strong> and referred to collectively as classical ciphers, could be encrypted and decrypted manually. This meant that, at that time, they did not obscure the data sufficiently to withstand the cryptanalysis tools.<\/p>\n<p>Three types of cryptography:<\/p>\n<ul>\n<li><strong>Symmetric key cryptography<\/strong> - a sender and receiver of a message employ a single common key to encrypt and decrypt the message.<\/li>\n<li><strong>Asymmetric key cryptography<\/strong> - a pair of keys is utilized to decrypt or encrypt data.<\/li>\n<li><strong>Hash functions<\/strong> - no need for any key. A hash value with a defined length is computed based on the plain text, making it difficult to reconstruct the plain text's contents.<\/li>\n<\/ul>\n<p>The rise of radio and internet communications resulted in the requirement for strong encryption since messages are now broadcasted promiscuously and could be hijacked at will.<\/p>","definition":"is an area of research and technique that secures data by prohibiting unauthorized third parties from accessing it.","status":"published","meta_title":"What is Cryptography? Definition & Meaning | Crypto Wiki","meta_description":"Cryptography meaning: Cryptography - is an area of research and technique that secures data by prohibiting unauthorized third parties from accessing it.","meta_keywords":null,"author":{"id":1,"user_id":1,"created_at":"2023-05-03T14:30:55.000000Z","updated_at":"2023-05-11T07:18:20.000000Z","title":"Editor-In-Chief","slug":"aaron-s-editor-in-chief","description":"<p>Having completed a Master’s degree on Economics, Politics & Culture for the East Asia region, Aaron has written scientific papers with a comparative analysis of the differences between US’ Western and Japan’s Collective forms of capitalism, 1945-2020.<\/p>\n<p>With close to a decade of experience in the FinTech industry, Aaron understands all of the biggest issues and struggles that crypto enthusiasts face. He’s a passionate analyst who is concerned with data-driven and fact-based content, as well as that which speaks to both Web3 natives and industry newcomers.<\/p>\n<p>Aaron is the go-to person for everything and anything related to digital currencies. With a huge passion for blockchain & Web3 education, Aaron strives to transform the space as we know it, and make it more approachable to complete beginners.<\/p>\n<p>Aaron has been quoted by multiple established outlets, and is a published author himself. Even during his free time, he enjoys researching the market trends, and looking for the next supernova.<\/p>","user":{"id":1,"first_name":"Aaron","last_name":"S.","email":"aaron@bitdegree.org","email_sanitized":"aaron@bitdegree.org","email_verified_at":"2023-12-01T09:40:20.000000Z","must_verify_email":false,"is_registered_with_wallet":false,"status":"active","country":"LT","last_connected_ip":"88.119.132.125","image_id":2641,"referral_token":"05TMu2NysXOCn525","referred_by":null,"created_at":"2023-05-03T14:30:55.000000Z","updated_at":"2024-01-09T15:22:21.000000Z","full_name":"Aaron S."}}}" :chapter-list="[{"id":1,"title":"Blockchain","slug":"blockchain","updated":null,"chapter":"crypto\/assets\/crypto-book\/chapters\/learn-blockchain.jpg","chapter_simple":"crypto\/assets\/crypto-book\/chapters-simple\/blockchain-101.jpg","rating":100,"sections":[{"chapter_id":1,"order":1,"slug":"what-is-blockchain","title":"What is the Blockchain?","status":"published","modified_content":null},{"chapter_id":1,"order":2,"slug":"decentralized-blockchain","title":"Anonymous & Decentralized Blockchains: The Cornerstone of Crypto","status":"published","modified_content":null},{"chapter_id":1,"order":3,"slug":"blockchain-transaction","title":"What is a Blockchain Transaction in Crypto?","status":"published","modified_content":null},{"chapter_id":1,"order":4,"slug":"crypto-fees","title":"The Different Types of Crypto Fees Explained","status":"published","modified_content":null},{"chapter_id":1,"order":5,"slug":"what-is-bridging-in-crypto","title":"The Key Notion Behind the Concept of Bridging in Crypto","status":"published","modified_content":null},{"chapter_id":1,"order":6,"slug":"types-of-blockchains","title":"Different Types of Blockchains: What to Look Out For?","status":"published","modified_content":null}]},{"id":2,"title":"Cryptocurrencies","slug":"cryptocurrencies","updated":null,"chapter":"crypto\/assets\/crypto-book\/chapters\/learn-cryptocurrencies.jpg","chapter_simple":"crypto\/assets\/crypto-book\/chapters-simple\/cryptocurrencies-101.jpg","rating":100,"sections":[{"chapter_id":2,"order":1,"slug":"what-is-a-cryptocurrency","title":"What is a Cryptocurrency?","status":"published","modified_content":null},{"chapter_id":2,"order":2,"slug":"how-does-cryptocurrency-work","title":"How Does Cryptocurrency Work?","status":"published","modified_content":null},{"chapter_id":2,"order":3,"slug":"is-cryptocurrency-a-good-investment","title":"Is Cryptocurrency a Good Investment? 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