W3Schools SQL

Beginner-friendly SQL tutorials with examples of queries, joins, constraints, and subqueries, plus an interactive editor.

The AI-Driven Leader

Erik R. Peterson

A guide to leveraging AI for smarter decision-making and leadership strategies

IBM Data Analyst Professional Certificate (Audit Free)

Covers data analysis with Excel, SQL, Python, and data visualization tools, including projects and case studies; free in audit mode.

Microsoft Learn - Data Analysis

Free learning paths covering data analysis basics and Power BI dashboards directly from Microsoft.

Manhattan Review Free GRE Resources

Free practice problems, diagnostic tests, and study tips from test prep experts.

Why Machines Learn

Anil Ananthaswamy

A deep dive into the elegant mathematical principles behind machine learning

FlowingData

Visualization-focused tutorials and guides on analyzing and presenting data effectively.

Enterprise DNA Blog

Tutorials and case studies focused on practical Power BI usage, advanced DAX, and visualization techniques.

CS50?s Introduction to Python

Harvard?s free course introducing programming using Python, with video lectures, notes, and problem sets.

edX - Data Analysis for Life Sciences

Harvard's free online courses teaching statistics, inference, modeling, and machine learning in the context of data science.

Kaggle Learn - Data Analysis

Hands-on mini-courses for Python, R, SQL, and visualization with Jupyter notebooks that run directly in the browser.

AI Engineering

Andrew Ng

A practical framework for building real-world AI applications from foundational principles

Analytics Vidhya

Wide range of free tutorials, guides, and case studies on data analytics, machine learning, and business intelligence.

Paul?s Online Math Notes

Comprehensive lecture notes, examples, and problem sets on calculus, differential equations, algebra, and more, written in an accessible format.

edX

edX is an American massive open online course provider created by Harvard and MIT. It hosts online university-level courses in a wide range of disciplines to a worldwide student body, including some courses at no charge.

W3Schools Python

Step-by-step interactive lessons for Python basics, data structures, and functions, with hands-on coding snippets.

HackerRank SQL Domain

SQL challenges of varying difficulty levels with instant online feedback, great for structured practice.

GeeksforGeeks Python Programming

Extensive collection of Python tutorials, code snippets, and explanations for basic to advanced topics, including algorithms.

Princeton Review GRE Practice

Free practice test access, strategy sessions, and sample GRE questions.

Stack Overflow - R Tag

A huge developer community answering detailed questions about R, packages, and applied statistics.