Big Data: a broad term for datasets so large or complex that traditional data processing applications are inadequate.
Moore's Law: a predication made by Gordon Moore in 1965 that computing power will double every 1.5-2 years, it has remained more or less true ever since.
Caesar Cipher : a technique for encryption that shifts the alphabet by some number of characters
Cipher: the generic term for a technique (or algorithm) that performs encryption
Cracking encryption: When you attempt to decode a secret message without knowing all the specifics of the cipher, you are trying to "crack" the encryption.
Decryption: a process that reverses encryption, taking a secret message and reproducing the original plain text
Encryption: a process of encoding messages to keep them secret, so only "authorized" parties can read it.
Random Substitution Cipher: an encryption technique that maps each letter of the alphabet to a randomly chosen other letters of the alphabet.
asymmetric encryption: used in public key encryption, it is scheme in which the key to encrypt data is different from the key to decrypt.
modulo: a mathematical operation that returns the remainder after integer division. Example: 7 MOD 4 = 3
Private Key: In an asymmetric encryption scheme the decryption key is kept private and never shared, so only the intended recipient has the ability to decrypt a message that has been encrypted with a public key.
Public Key Encryption: Used prevalently on the web, it allows for secure messages to be sent between parties without having to agree on, or share, a secret key. It uses an asymmetric encryption scheme in which the encryption key is made public, but the decryption key is kept private.
symmetric encryption: an encryption scheme in which the key used to encrypt data is also used to decrypt (contrast with: asymmetric encryption)
Antivirus Software: usually keeps big lists of known viruses and scans your computer looking for the virus programs in order to get rid of them.
DDoS Attack: Distributed Denial of Service Attack. Typically a virus installed on many computers (thousands) activate at the same time and flood a target with traffic to the point the server becomes overwhelmed.
Firewall: software that runs on servers (often routers) that only allows traffic through according to some set of security rules.
Phishing Scam: a thief trying to trick you into sending them sensitive information. Typically these include emails about system updates asking you send your username and password, social security number or other things.
SSL/TLS: Secure Sockets layer / Transport Layer Security - An encryption layer of HTTP that uses public key cryptography to establish a secure connection.
Virus: a program that runs on a computer to do something the owner of the computer does not intend.