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What is encryption? 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How it works + types of encryption What is encryption? How it works + types of encryption What is encryption? Encryption converts sensitive information or data into a secret code to prevent unauthorized access. Written by Clare Stouffer Published July 18, 2023 3 min read Contents What is encryption? How does encryption work? Types of encryption What is an encryption algorithm? 6 types of encryption algorithms How does encryption keep internet browsing secure? Why you need encryption Can scammers use encryption to commit cybercrimes? FAQs about encryption If you’ve ever made an online purchase, logged in to your social media accounts, or filled out an online contact form, your information already exists as encrypted data. Encryption is an essential online privacy tool used to safeguard sensitive, confidential, or personal information across the internet. Encryption scrambles plain text into a type of secret code that hackers, cybercriminals, and other online snoops can't read—even if they intercept it before it reaches its intended recipients. When the message gets to its recipients, they have their own key to unscramble the information back into plain, readable text. With one in three consumers falling victim to cybercrimes in 2021 alone, simple security measures like encryption can help protect the data you send, receive, and store on your electronic devices. What is encryption? Encryption is a cybersecurity measure that scrambles plain text so it can only be read by the user who has the secret code, or decryption key. It provides added security for sensitive information. Huge amounts of data are managed online and stored in the cloud or on servers with an ongoing connection to the web. It’s nearly impossible to do anything online—from purchasing new office chairs to logging in to your HR portal—without your personal data ending up in an organization’s networked computer system. That’s why it’s crucial to know how to help keep that personal information private . Encryption plays an essential role in this task. When to use encryption It’s important to encrypt messages, files, and data exchanged online whenever they contain personal, sensitive, or classified information like: Sending an email to your doctor regarding an illness Entering your financial information to log in to your online bank account Sharing a confidential report with your employer Encryption ensures only the intended recipient can access the information you shared. How does encryption work? Encryption takes plain text, like a text message or email, and scrambles it into an unreadable format called ciphertext . This helps protect the confidentiality of digital data either stored on computer systems or transmitted through a network like the internet. When the intended recipient accesses the message, the information is translated back to its original form. This is called decryption . To unlock the message, both the sender and the recipient have to use a “secret” encryption key —a collection of algorithms that scramble and unscramble data back to a readable format. Types of encryption An encryption key is a series of numbers used to encrypt and decrypt data. Encryption keys are created with algorithms, and each key is random and unique. There are two main types of encryption systems: symmetric encryption and asymmetric encryption. Here’s how they differ. Symmetric encryption Symmetric encryption uses a single secret password or key to encrypt and decrypt data. The key could be a code or a random string of letters or numbers generated by a random number generator (RNG), which is typically required for banking-grade encryption. Symmetric algorithms are the simplest and most used form of encryption. Symmetric encryption algorithms are available in two forms: Block algorithms: Encrypt a group of plain text symbols as one block. Stream algorithms: Convert one symbol of plain text directly into ciphertext. Although symmetric encryption has its weak spots, it makes up for them in speed and efficiency. Since only one key is shared between parties—and that key is typically much shorter than with asymmetric encryption— symmetric cryptography is faster to run. Asymmetric encryption Asymmetric encryption—also known as public key cryptography—uses two keys for encryption and decryption. A public key, which is shared among users, can either encrypt or decrypt the data. A private key can also encrypt or decrypt data, but it's not shared among users. The key you choose to encrypt or decrypt depends on the security measure you’re trying to employ: Encrypting with the public key: ensures only the intended recipient can use the corresponding private key to decrypt the message, even if the information was breached during transit Encrypting with the private key: allows the recipient of the information to verify the sender’s identity, since they won’t be able to decrypt data that’s been tampered with by an unauthorized user Because asymmetric encryption uses two longer keys, it’s much slower and less efficient to run compared to symmetric cryptography. It can even bog down networks and create issues with memory capacity and battery life. However, asymmetric encryption is considered more advanced in terms of security than symmetric cryptography. Both are still in use today—sometimes simultaneously to compensate for the other’s weaknesses. What is an encryption algorithm? An encryption algorithm is a set of rules, usually governing a computer or other tech device such as a smartphone, that turns readable data into scrambled ciphertext . The data scrambled by these algorithms look like randomized code, but the algorithms configure this scrambled data in a purposeful way so that it can easily be turned back into a readable format by a decryption key. 6 types of encryption algorithms There are several types of encryption, some stronger than others. Here are the most common examples of encryption algorithms. Data Encryption Standard (DES) Data Encryption Standard is an outdated symmetric encryption standard created in 1977 to protect government agencies. The system’s key length was a mere 56 bits—not nearly enough to keep cybercriminals from cracking the code. In 1999, it took engineers just 22 hours to hack a DES system. With modern tech, a 56-bit DES key can crack in as little as six minutes. Because of advances in technology and decreases in the cost of hardware, DES is essentially obsolete for protecting sensitive data. Triple DES (3DES) Triple DES is a symmetric key block cipher that runs DES encryption three times. It encrypts, decrypts, and re-encrypts data—hence the name. It strengthens the original DES standard, which is now viewed by security experts as too weak for sensitive data. However, even 3DES does not meet today’s security standards. With more effective algorithms available, like AES, the National Institute of Standards and Technology plans to deprecate DES and 3DES for all applications by the end of 2023. Advanced Encryption Standard (AES) Known for its impressive combination of speed and security, AES is the industry standard for encryption. AES uses both symmetric encryption and a substitution permutation network (SPN) algorithm to apply multiple rounds of encryption. These encryption rounds aid in security, since there are simply too many rounds for a cybercriminal to break through. Cracking a 128-bit AES key can take up to 36 quadrillion years. The Advanced Encryption Standard replaced DES in 2002 as the U.S. government standard. Rivest-Shamir-Adleman (RSA) RSA takes its name from the surname initials of the three computer scientists who created it. This asymmetric system gives users the option to encrypt with either a public or private key, making it ideal for sending private data across the internet. When the public key is used for encryption, only the intended recipient can use the private key to decrypt it, even if the information was breached during transit. On the other hand, encrypting with the private key allows the recipient of the information to verify the sender’s identity. If the data was stolen and modified in transit, the recipient wouldn’t be able to decrypt the new message with the public key, so they’d know it’d been tampered with. Twofish Twofish is considered one of the fastest symmetric encryption algorithms and is free for anyone to use. The system relies on a 128-bit key, making it almost impenetrable to brute force attacks—it could take decades for a hacker to decrypt one single message. It’s ideal for both hardware and software. Elliptic curve cryptography (ECC) Considered the next generation of cryptography, ECC is an asymmetric encryption algorithm that uses the mathematics behind elliptic curves. This method is almost impossible to crack since there is no known solution to the mathematical problem the algorithm is based on. This provides a significantly more secure connection tha