Technical Lexicon

The AI Glossary

Master the concepts driving the future of artificial intelligence. From foundational algorithms to complex neural architectures, navigate the terminology of modern AI.

Fundamentals

4 Terms

Machine Learning

8 Terms
Beginner

Machine Learning (ML)

A subfield of AI that develops algorithms allowing machines to learn patterns from data and make predictions or decisions — without being explicitly programmed for each scenario.

Beginner

Data Science

An interdisciplinary field combining statistics, programming, and domain expertise to extract knowledge and actionable insights from structured and unstructured data.

Beginner

Supervised Learning

A Machine Learning paradigm where a model is trained on a labeled dataset — examples with known correct answers — so it can learn to make predictions on new, unseen data.

Intermediate

Unsupervised Learning

A Machine Learning paradigm that works with unlabeled data, discovering hidden patterns, structures, or groupings on its own — without predefined correct answers.

Intermediate

Reinforcement Learning (RL)

A Machine Learning paradigm where an agent learns to make decisions by interacting with an environment, receiving rewards for good actions and penalties for bad ones, seeking to maximize cumulative reward over time.

Intermediate

Semi-supervised Learning

A learning paradigm that combines a small amount of labeled data with a large amount of unlabeled data during training, achieving better performance than purely supervised or unsupervised approaches alone.

Intermediate

Overfitting

A modeling failure where a machine learning model learns the training data too closely — memorizing noise and edge cases — and subsequently performs poorly on new, unseen data.

Intermediate

Cross-Validation

A model evaluation technique that divides data into multiple subsets, repeatedly training on some and testing on the remainder, to obtain a more reliable, unbiased estimate of model performance.

Intermediate

Feature Engineering

The process of selecting, transforming, or creating input variables (features) from raw data to make machine learning algorithms work more effectively on a given problem.

Intermediate

Hyperparameter Tuning

The process of systematically optimizing the configuration settings of a machine learning algorithm — settings set before training, not learned from data — to maximize model performance.

Deep Learning

10 Terms
Intermediate

Deep Learning (DL)

A subfield of Machine Learning that uses artificial neural networks with many layers to learn extremely complex patterns directly from raw data — such as images, audio, and text.

Intermediate

Artificial Neural Network (ANN)

A computational model inspired by the human brain, composed of interconnected layers of nodes (neurons) that process information and learn complex mappings from inputs to outputs.

Intermediate

Activation Function

A mathematical function applied to each neuron's output that introduces non-linearity, enabling neural networks to learn complex, non-linear patterns rather than just linear combinations of inputs.

Advanced

Backpropagation

The foundational algorithm for training neural networks — it efficiently computes the gradient of the loss function with respect to every weight in the network, enabling gradient-based optimization.

Intermediate

Gradient Descent

An iterative optimization algorithm that minimizes a loss function by updating model parameters in small steps in the direction opposite to the gradient — progressively reducing prediction error.

Intermediate

Convolutional Neural Network (CNN)

A neural network architecture specialized for grid-structured data (especially images) that uses learned filters to detect local features — edges, textures, shapes — in a hierarchical, spatially-aware manner.

Intermediate

Recurrent Neural Network (RNN)

A neural network architecture designed for sequential data that maintains a hidden state — a form of memory — allowing it to incorporate context from previous inputs when processing each new element.

Advanced

LSTM / GRU

Advanced Recurrent Neural Network variants that use gating mechanisms to selectively retain or forget information — overcoming the vanishing gradient problem and enabling learning of long-term dependencies in sequences.

Advanced

Transformer

A neural network architecture that processes entire sequences in parallel using self-attention mechanisms — eliminating recurrence and enabling the large-scale training that underlies modern LLMs and many state-of-the-art AI systems.

Advanced

Attention Mechanism

A technique that allows neural networks to dynamically focus on the most relevant parts of an input when producing each element of the output — enabling models to capture long-range dependencies without recurrence.

Intermediate

Dropout

A regularization technique that randomly deactivates a fraction of neurons during each training step, forcing the network to learn more robust, distributed representations and reducing overfitting.

Generative AI

8 Terms
Beginner

Generative AI

A branch of AI focused on models that generate new, original content — text, images, audio, code, video — that is statistically similar to the data they were trained on.

Intermediate

Large Language Model (LLM)

A Transformer-based deep learning model trained on massive text corpora — capable of understanding, generating, translating, summarizing, and reasoning about human language at unprecedented scale.

Advanced

Generative Adversarial Network (GAN)

A generative model architecture composed of two competing neural networks — a generator that creates synthetic data and a discriminator that attempts to detect fakes — trained together in a minimax game until outputs become indistinguishable from real data.

Advanced

Variational Autoencoder (VAE)

A generative model that learns to encode data into a structured, continuous latent space and decode it back — enabling generation of new, similar data points by sampling from that learned space.

Beginner

ChatGPT

A conversational AI assistant developed by OpenAI, built on the GPT family of large language models and aligned with human preferences through RLHF — designed for natural, multi-turn dialogue and a wide range of text-based tasks.

Intermediate

GPT (Generative Pre-trained Transformer)

A family of large language models developed by OpenAI using the Transformer decoder architecture, pre-trained on massive text datasets to predict the next token — forming the foundation for ChatGPT and many AI applications.

Intermediate

BERT

Bidirectional Encoder Representations from Transformers — Google's landmark language model that reads text bidirectionally, capturing richer contextual understanding than left-to-right models, and became the foundation for NLP fine-tuning.

Intermediate

Fine-tuning

The process of adapting a large pre-trained model to a specific task or domain by continuing its training on a smaller, task-specific dataset — leveraging the general knowledge already encoded in the model.

Beginner

Prompt Engineering

The practice of designing, refining, and structuring inputs (prompts) given to AI language models to elicit the most accurate, relevant, and useful responses — without modifying model weights.

Applications

5 Terms
Beginner

Computer Vision

A field of AI that enables machines to interpret and understand visual information from images and video — detecting objects, recognizing faces, reading scenes, and extracting actionable insights from pixels.

Beginner

Natural Language Processing (NLP)

A field of AI dedicated to enabling computers to understand, interpret, generate, and reason about human language — in text and speech form — powering applications from chatbots to translation systems.

Intermediate

Object Detection

A computer vision task that identifies and locates multiple objects within an image or video, typically outputting both a class label and a bounding box for each detected instance.

Advanced

Semantic Segmentation

A computer vision task that classifies every pixel of an image into a semantic category, producing a dense map that labels each pixel as belonging to a road, building, sky, person, or any other class.

Beginner

Sentiment Analysis

An NLP technique that automatically determines the emotional tone or opinion expressed in text — typically classifying it as positive, negative, or neutral — to extract subjective insights at scale.

Intermediate

Named Entity Recognition (NER)

An NLP task that identifies and classifies named entities in text — such as people, organizations, locations, dates, and monetary values — enabling structured extraction from unstructured language.

Ethics & Society

7 Terms
Beginner

AI Ethics

The field that establishes principles and frameworks to guide the development and deployment of AI systems in ways that are fair, transparent, accountable, and respectful of human rights and values.

Intermediate

Algorithmic Bias

The tendency of AI systems to produce systematically unfair or discriminatory outcomes for certain groups — arising from biased training data, flawed model assumptions, or the contexts in which systems are deployed.

Advanced

Fairness

An AI ethics principle and active research area focused on ensuring AI systems produce equitable outcomes across demographic groups — a goal that involves irresolvable trade-offs between competing mathematical definitions of what 'fair' actually means.

Intermediate

Explainable AI (XAI)

A set of methods and principles aimed at making AI model decisions interpretable and transparent to humans — enabling auditing, debugging, regulatory compliance, and trust in AI systems.

Advanced

AI Alignment Problem

The fundamental challenge of ensuring that advanced AI systems pursue goals and exhibit behaviors that are genuinely aligned with human values and intentions — especially as systems become more capable and autonomous.

Intermediate

AI Safety

An interdisciplinary research field focused on ensuring that AI systems are reliable, controllable, and beneficial — addressing both near-term risks from current systems and long-term risks from potentially transformative future AI.

Advanced

Technological Singularity

A hypothetical future point at which technological progress — particularly AI-driven recursive self-improvement — becomes so rapid and transformative that it fundamentally and irreversibly alters human civilization in ways that cannot be predicted from our current vantage point.

Technical Concepts

8 Terms
Beginner

Algorithm

A finite, well-defined sequence of instructions or rules that takes an input, performs a series of computational steps, and produces an output — the foundational building block of all computing and AI systems.

Beginner

Training Data

The dataset used to train a machine learning model — the examples from which the model learns the statistical patterns, relationships, and representations it will use to make predictions on new data.

Beginner

Test Data

A held-out dataset used exclusively to evaluate a trained model's performance on unseen examples — providing an unbiased estimate of how the model will perform in the real world.

Intermediate

Loss Function

A mathematical function that quantifies the difference between a model's predictions and the true values — the signal that guides the learning process by telling the model how wrong it is and in which direction to improve.

Beginner

Epoch

One complete pass through the entire training dataset during model training — a unit of training progress used to track how many times every training example has been seen by the model.

Intermediate

Batch Size

The number of training examples processed together in a single forward and backward pass during model training — a hyperparameter that balances training speed, memory usage, and gradient estimate quality.

Intermediate

Learning Rate

A hyperparameter that controls the size of the weight updates during gradient descent — determining how quickly or slowly a model learns from its training data.

Beginner

Inference

The process of using a trained machine learning model to make predictions or generate outputs on new, unseen data — the production phase that follows training and deployment.