Lecture Notes on Digital Technology, Networking, and Security

Flashcards covering key vocabulary and concepts from lecture notes on digital technology, networking, and security.

Digital Divide

Unequal access to computers and the Internet based on poverty, racism, sexism, isolation in the countryside, age, and other factors, affecting individuals and countries.

Citizen Science

Scientific research conducted by distributed individuals, many not scientists, who contribute data to research using their own computing devices.

Crowdsourcing

Using the Internet to get a lot of people to help solve a problem. Citizen science is a type of this.

Computing Innovation

Can be physical, non-physical software, or conceptual, but must include a program as an integral part of its function.

Binary Sequence

A string of ones and zeros.

Analog

Data with values that change smoothly, unlike digital data which change in discrete intervals.

Sampling

Measuring values, called samples, of an analog signal at regular intervals.

Sampling Rate

The number of samples measured per second.

Width

The number of bits that a CPU processes at a time.

Word

A binary sequence of the number of bits processed by a CPU at one time; typically 32 bits or 64 bits.

Floating Point

Uses powers of two to represent very large or very small values.

Bit

A single unit of data that can only have one of two values, typically represented as 0 (off) and 1 (on). Abbreviation for binary digit.

Byte

Eight bits.

Lossless Compression

Data compression algorithms that are reversible; you can reconstruct the original data.

Lossy Compression

Data compression algorithms that are not fully reversible; you can reconstruct only an approximation of the original data.

Encryption

The process of encoding data to prevent unauthorized access.

Decryption

The process of decoding data.

Symmetric Encryption

Encryption using the same key for both encryption and decryption.

Public Key Encryption

Encryption using a pair of keys: a public key for encryption and a private key for decryption.

SSL/TLS

The standard used for cryptographically secured information transfer on the Internet.

Certificate Authorities

Organizations that issue digital certificates to verify who owns the encryption keys used for secured communications.

Malware

Software that was designed to harm or take partial control over your computer.

Keylogging Software

A kind of malware that records every key pressed by a user.

Computer Virus

A type of malware that spreads and infects other computers. Can attach themselves to legitimate programs.

Antivirus Software

Software designed to scan your files and Internet transmissions looking for malware.

Firewall

A security system that controls the kinds of connections that can be made between a computer or network and the outside world.

Phishing

A security attack in which the victim is tricked into giving up personal information or downloading malware.

DDoS Attack

An attack that uses a virus to flood a server with many requests from many computers at once so that users of that server are denied service.

Rogue Access Point

A wireless access point that gives access to a secure network without the authorization of the network administrator.

Personally Identifiable Information (PII)

Information that can let others figure out who you are and possibly get more information, such as Social Security number, age, race, phone number(s), etc.

Creative Commons

A specific family of copyright licenses that allow others to use, share, maybe sell, and maybe revise your work.

Free Software

Software that anyone can copy, use, modify, and redistribute, including commercially, provided that any modifications must be under the same license.

Open Source

A more general term that means that you make the program's source (human-readable) code available to anyone. You may still restrict how people can use the program.

Open Access

Scholarly research reports are available for free download, rather than requiring the permission of a journal publisher.

Internet

A computer network that uses open protocols to standardize communication. Requires a computing device connected to an Internet-connected device to access.

Computer Network

An interconnected computing system that is capable of sending or receiving data.

Computing System

A group of computing devices and programs working together for a common purpose.

Computing Device

A physical object that can run a program, such as computers, tablets, cell phones, and smart sensors.

World Wide Web

A system of linked pages, programs, and files that uses the Internet.

Router

A computer that passes information from one network to another.

ISPs

The companies who sell Internet access to homes and institutions.

Bandwidth

The maximum amount of data that can be sent in a fixed amount of time (measured in bits per second).

The Cloud

Storing data somewhere on the Internet, but you don't know where. The cloud service provider manages the actual storage location.

Path

A sequence of directly connected computing devices that connect a sender to a receiver.

Routing

The process of finding a path from sender to receiver.

Scalability

The ability of the Internet to keep working as it grows.

Redundancy

The inclusion of back-up elements in case one part fails.

Fault Tolerance

The ability of a system to work around problems.

Protocol

A set of rules that specify the behavior of a system.

IP Address

A unique number assigned to each device on a computer network.

Packet

A small chunk of any kind of data and metadata that is passed through the Internet as a data stream.

Packet Switching

Means that the Internet sends short bursts of information, not long continuous strings.

TCP/IP

A pair of protocols that provide two levels of abstraction; IP and TCP.