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Artificial Intelligence

Practical Intelligence, Humans in Control.

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6connected topics
28practical lessons
3learning levels
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PLAIN LANGUAGE. USEFUL DETAIL.

Your AI glossary.

Expand a term to understand what it means.

47 terms

Activation function

A transformation applied to a neuron’s input sum. Nonlinear activations let networks model nonlinear relationships.

Agent

A system that selects actions toward a goal using observations and available tools; the term has several definitions.

Attention

A mechanism that computes weighted combinations of representations, often across sequence positions.

Backpropagation

An efficient application of the chain rule to compute gradients through a computational graph.

Bias (parameter)

An adjustable offset in a model. This is distinct from unfairness or statistical bias.

Calibration

Agreement between predicted probabilities and observed frequencies across comparable predictions.

Classification

Predicting a category or category probabilities from input data.

Clustering

Grouping examples using a chosen representation and similarity rule, without supplied cluster labels.

Constraint

A restriction a solution must satisfy; soft constraints instead express preferences.

Context window

The bounded amount of input and generated content a model can consider in one interaction.

Convolution

A local operation that applies shared filter weights across positions, commonly used in image models.

Data leakage

Use of information during training or evaluation that would not legitimately be available at prediction time.

Deep learning

Machine learning using neural networks with multiple processing layers.

Distribution shift

A difference between the data distribution used for development and the one encountered later.

Embedding

A numerical vector representation whose learned relationships can support tasks such as similarity search.

Epoch

One pass through the training dataset; it is not a universal unit of model quality.

Feature

An input measurement or representation used by a model.

Fine-tuning

Training that updates some or all parameters of an already trained model for a task or domain.

Generative AI

Systems that produce content such as text, images or audio using learned patterns.

Gradient

A vector of partial derivatives describing local change in a scalar function.

Grounding

Connecting an answer to relevant evidence or inputs; it does not guarantee the answer is correct.

Hallucination

Generated content that is unsupported or incorrect despite appearing plausible.

Heuristic

A rule or estimate used to guide a problem-solving process, such as estimated remaining path cost.

Inference

Applying a model or reasoning procedure to inputs; in ML this usually uses already fitted parameters.

Label

The target outcome associated with a supervised training example.

Learning rate

A setting controlling the size of optimizer updates during training.

Loss

A numerical training objective measuring prediction error or other desired behavior.

Model

A mathematical or computational representation used to produce predictions, content or decisions.

Neural network

A parameterized network of transformations, typically trained using examples.

Overfitting

Learning training-specific details that do not generalize well to unseen data.

Parameter

A fitted value inside a model, such as a weight or bias.

Policy

In decision-making systems, a rule or learned mapping that selects actions from observations or states.

Precision

True positives divided by all predicted positives, when the denominator is nonzero.

Prompt injection

An attempt to make a system treat untrusted content as instructions that change its authorized behavior.

RAG

Retrieval-augmented generation: retrieving external material and using it as context for generation.

Recall

True positives divided by all actual positives, when the denominator is nonzero.

Regression

Predicting a numeric outcome, such as demand or travel time.

Regularization

Techniques that constrain learning to improve generalization rather than merely fit training data.

Reinforcement learning

Learning a policy from reward signals associated with actions and resulting transitions.

Softmax

A function that maps a vector of scores to nonnegative values summing to one.

Supervised learning

Learning from examples paired with target outcomes.

Test set

Data reserved for final evaluation after development choices are fixed.

Token

A unit used to represent content in a model; it may be a word fragment, symbol or other encoded element.

Transformer

A neural architecture based on attention and other components, with variants for different tasks.

Unsupervised learning

Learning structure without supplied target labels for the main learning task.

Validation set

Data used during development to compare models and select settings.

Workflow

A defined sequence or graph of processing steps; it can use AI without granting open-ended action selection.

How to use these lessons

01 · UnderstandChoose a level. Beginner uses everyday language; Intermediate connects the concepts; Advanced adds mathematical and system-level details.

02 · PracticeWork through each fictional example and exercise. Open the answer guide when you are ready, then try the advanced challenge.

03 · DiscussFollow a lesson’s forum search to find relevant conversations. If none exists, use the community to ask a new question. No posts are created automatically.

Advanced lessons assume basic algebra and familiarity with the preceding concepts. Completion marks are personal bookmarks, not qualifications or assessments.