> ## Documentation Index
> Fetch the complete documentation index at: https://freelance-4888ed08.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Glossary

> Plain-English explanations of every technical term used in the Demand Forecasting System documentation

> [!NOTE]
>
> **For non-technical readers:** This page explains every technical term used across the documentation in plain English. Bookmark this page as a quick reference.

## Machine Learning & AI

| Term | Plain English | Where Used |
| - | - | - |
| **Machine Learning (ML)** | Software that learns patterns from historical data to make predictions about the future | Everywhere |
| **MLOps** | The practice of managing ML models like software products — versioning, deploying, and monitoring them in production | Everywhere |
| **CatBoost** | A prediction algorithm ("model") that excels at learning from mixed data types — numbers and categories together | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **Regression** | A type of prediction that outputs a number (e.g., "142 bikes will be rented") rather than a category | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **Hyperparameters** | Settings that control how the model learns — like tuning dials on a radio to get the clearest signal | [Parameters](https://freelance-4888ed08.mintlify.site/configuration/parameters.md) |
| **Bayesian Optimization** | A smart method for finding the best hyperparameters by learning from previous results rather than testing randomly | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **RMSE** | Root Mean Square Error — a measure of how far predictions are from actual values. Lower is better | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **SHAP** | A method that explains *why* the model made a specific prediction by showing which factors mattered most | [Explainability](https://freelance-4888ed08.mintlify.site/ml-solution/explainability.md) |

## Data & Features

| Term | Plain English | Where Used |
| - | - | - |
| **Feature** | A piece of information the model uses to make predictions (e.g., temperature, hour of day, humidity) | [Feature Engineering](https://freelance-4888ed08.mintlify.site/ml-solution/feature-engineering.md) |
| **Feature Engineering** | The process of creating new data columns from existing ones to help the model learn better | [Feature Engineering](https://freelance-4888ed08.mintlify.site/ml-solution/feature-engineering.md) |
| **Lag Features** | Values from previous time periods — e.g., "how many bikes were rented 1 hour ago?" — that help predict future demand | [Feature Engineering](https://freelance-4888ed08.mintlify.site/ml-solution/feature-engineering.md) |
| **Data Pipeline** | An automated sequence of steps that collects, validates, cleans, and prepares data for the model | [Data Pipeline](https://freelance-4888ed08.mintlify.site/ml-solution/data-pipeline.md) |
| **Data Catalog** | A registry listing every dataset in the system, its format, and where it's stored | [Data Catalog](https://freelance-4888ed08.mintlify.site/configuration/data-catalog.md) |
| **Pandera** | A library that enforces data quality rules — rejecting bad data before it reaches the model | [Data Pipeline](https://freelance-4888ed08.mintlify.site/ml-solution/data-pipeline.md) |
| **Data Drift** | When real-world data stops matching what the model was trained on, causing predictions to degrade | [Data Quality](https://freelance-4888ed08.mintlify.site/ml-solution/data-quality-and-drift.md) |

## Infrastructure & Deployment

| Term | Plain English | Where Used |
| - | - | - |
| **Docker** | Technology that packages software into standardized containers that run identically everywhere | [Infrastructure](https://freelance-4888ed08.mintlify.site/deployment/infrastructure.md) |
| **Docker Compose** | A tool for running multiple Docker containers (services) together as one system | [Infrastructure](https://freelance-4888ed08.mintlify.site/deployment/infrastructure.md) |
| **Container** | A lightweight, isolated package containing everything needed to run a piece of software | [Infrastructure](https://freelance-4888ed08.mintlify.site/deployment/infrastructure.md) |
| **API** | Application Programming Interface — a way for software to request predictions or data from the system | [API Reference](https://freelance-4888ed08.mintlify.site/api-reference/openapi.md) |
| **FastAPI** | The Python framework powering the prediction API — known for speed and automatic documentation | [Inference](https://freelance-4888ed08.mintlify.site/deployment/inference.md) |
| **Endpoint** | A specific URL where the API accepts requests (e.g., `/predict` for generating forecasts) | [API Reference](https://freelance-4888ed08.mintlify.site/api-reference/predict.md) |
| **Rate Limiting** | Restricting how many API requests a user can make per minute to prevent abuse | [Inference](https://freelance-4888ed08.mintlify.site/deployment/inference.md) |
| **Argon2id** | An industry-standard password hashing algorithm used to securely verify API keys | [Inference](https://freelance-4888ed08.mintlify.site/deployment/inference.md) |

## Orchestration & Automation

| Term | Plain English | Where Used |
| - | - | - |
| **Airflow** | A scheduling platform that runs automated workflows on a timetable, like a smart cron job | [Orchestration](https://freelance-4888ed08.mintlify.site/ml-solution/orchestration.md) |
| **DAG** | Directed Acyclic Graph — a visual representation of a workflow showing which steps depend on others | [Orchestration](https://freelance-4888ed08.mintlify.site/ml-solution/orchestration.md) |
| **Kedro** | A Python framework for building reproducible data science pipelines with clear structure | [Data Pipeline](https://freelance-4888ed08.mintlify.site/ml-solution/data-pipeline.md) |
| **Optuna** | A tool that automatically searches for the best model settings using Bayesian optimization | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **Automated Retraining** | The system's ability to detect performance degradation and retrain the model without human intervention | [Retraining](https://freelance-4888ed08.mintlify.site/ml-solution/automated-retraining.md) |

## Monitoring & Observability

| Term | Plain English | Where Used |
| - | - | - |
| **Prometheus** | A system that collects and stores metrics (numbers) about system health — CPU, memory, request counts | [Operations](https://freelance-4888ed08.mintlify.site/ml-solution/operations-reliability.md) |
| **Grafana** | A dashboard tool that visualizes Prometheus metrics with charts, graphs, and alerts | [Operations](https://freelance-4888ed08.mintlify.site/ml-solution/operations-reliability.md) |
| **MLflow** | A platform for tracking experiments, versioning models, and managing the model lifecycle | [Experiments](https://freelance-4888ed08.mintlify.site/ml-solution/experiments.md) |
| **MinIO** | An S3-compatible object storage system used to store model files and data artifacts | [Infrastructure](https://freelance-4888ed08.mintlify.site/deployment/infrastructure.md) |
| **Evidently** | A monitoring library that detects data drift using statistical tests (like the KS-test) | [Retraining](https://freelance-4888ed08.mintlify.site/ml-solution/automated-retraining.md) |
| **KS-test** | Kolmogorov-Smirnov test — a statistical method that measures if two data distributions are different | [Data Quality](https://freelance-4888ed08.mintlify.site/ml-solution/data-quality-and-drift.md) |

## Metrics & Evaluation

| Term | Plain English | Where Used |
| - | - | - |
| **MAE** | Mean Absolute Error — average difference between predicted and actual values. Easier to interpret than RMSE | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **R² Score** | How well the model explains the variation in data. 1.0 = perfect, 0.0 = no better than guessing the average | [Training](https://freelance-4888ed08.mintlify.site/ml-solution/training-optimization.md) |
| **PSI** | Population Stability Index — measures how much the data distribution has shifted over time | [Operations](https://freelance-4888ed08.mintlify.site/ml-solution/operations-reliability.md) |
| **A/B Testing** | Splitting traffic between two models to compare which performs better in production | [Inference](https://freelance-4888ed08.mintlify.site/deployment/inference.md) |

***

## Related Pages

> [card] [Problem Statement](https://freelance-4888ed08.mintlify.site/introduction/problem-statement.md)
>
> Business context and objectives behind the forecasting system.

> [card] [System Overview](https://freelance-4888ed08.mintlify.site/architecture/system-overview.md)
>
> High-level architecture showing how all components connect.


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