IB Computer Science

Abstraction can be defined as hiding intricate details beneath a simpler, more manageable layer (or interface).

Abstraction is the process of hiding implementation details and exposing only the essential features of an object.

Focusing on the essential features of a problem and removing the details that do not affect the outcome, leaving a simplified model that can be reused on similar problems.

The four guarantees a database makes about every transaction: atomicity, consistency, isolation and durability. Together they ensure that grouped operations are processed reliably and leave the data in a valid state.

The function a node applies to its weighted sum to produce its output. It introduces non-linearity, which is what allows a network of layers to model more than a single straight boundary.

Devices that effect changes in a system based on controller signals.

A SQL function that reads the values of a column across many rows and returns one summary value. The five named in the syllabus are AVERAGE (written AVG in most systems), COUNT, MAX, MIN and SUM.

A step-by-step set of clear, precise and unambiguous instructions that solves a problem or produces a required outcome. It can be written as sentences, pseudocode or a flowchart before it becomes code.

The property of a machine learning system whose outcomes do not depend on group membership such as sex, ethnicity or age.

The application layer provides the interface between applications and the network.

An application-specific integrated circuit (ASIC) is a chip designed and fabricated to carry out one fixed task. It cannot be reprogrammed after manufacture, which is what makes it fast and power-efficient on that task and useless if the task changes.

A method for association rule learning that first finds every itemset meeting a minimum support, then builds rules from those itemsets and keeps the ones meeting a minimum confidence. It prunes the search using the property that any set containing an infrequent itemset must itself be infrequent.

A fixed-size, ordered collection of elements that all share the same data type. Each element is reached by an integer index that starts at 0, and the length is set when the array is created.

A computational model built from interconnected nodes, or neurons, loosely inspired by the brain.

An if-then statement reporting that two sets of items tend to appear in the same transaction, written $\{\text{antecedent}\} \Rightarrow \{\text{consequent}\}$. It records co-occurrence in the data and makes no claim about cause.

Asymmetric cryptography gives each party a mathematically linked key pair: a public key that can be published to anyone and a private key that never leaves its owner. It solves key distribution but is far slower than symmetric cryptography.

Attenuation is the loss of signal strength as a signal travels through a transmission medium. It sets how far a link can run before the signal has to be regenerated by a repeater or a switch.

A technology that overlays digital content such as images, sounds, or data onto the real-world environment, enhancing how users perceive and interact with their surroundings.

Autonomous vehicles are complex control systems that rely on a sophisticated interplay of sensors, algorithms, and actuators.

The training step that works backwards from the loss at the output layer, calculating how much each weight and bias contributed to the error so gradient descent can adjust them.

Bandwidth is the maximum amount of data a link can carry per second, usually measured in bits per second. On a shared medium such as wireless it is divided between all the devices using the same channel.

An unfair tendency for or against particular individuals or groups. In machine learning it is learned from patterns already present in the training data.

A learned constant added to a node's weighted sum, which shifts the threshold at which the node fires so its decision boundary need not pass through the origin.

Binary is a base-2 number system, using only two digits: 0 and 1. Each digit in a binary number is called a bit (short for binary digit).