GeeksforGeeks Python Programming
Extensive collection of Python tutorials, code snippets, and explanations for basic to advanced topics, including algorithms.
King?s Wargaming Network
Academic network advancing theory and application of wargaming for research and teaching within Security Studies.
RADACAD Power BI Blog
Practical tutorials and tips on Power BI modeling, DAX, Power Query, and real-world scenarios written by MVPs.
HackerRank SQL Domain
SQL challenges of varying difficulty levels with instant online feedback, great for structured practice.
Magoosh GRE Blog
Hundreds of free articles, study guides, vocabulary lists, and strategies for GRE verbal, quant, and writing.
SQL Shack ? Power BI
Collection of practical Power BI tutorials and tips, especially useful for SQL Server professionals integrating BI dashboards.
Art of Problem Solving (AoPS) Online Resources
Challenging problems, explanations, and articles designed for advanced high school and college-level students interested in problem solving and Olympiad-style math.
Coursera - Math for Machine Learning (Audit Free)
University of London courses on linear algebra, multivariate calculus, and statistics for machine learning, available free in audit mode.
SQLite Tutorial
Focused tutorials on SQLite, covering SQL basics, database management, and practical coding examples.
UC Berkeley Data 8 (Foundations of Data Science)
Introductory data science/analytics course using Python; includes lectures, labs, and exercises for free online.
OpenIntro Statistics
Free, open-source statistics textbook with R labs and applied data analysis examples.
Marine Corps Warfighting Lab ? Wargaming Division
USMC wargaming division supporting concept development and force design through iterative gaming and analysis.
Naval War College ? Wargaming Department
Department page describing applied gaming, methods, and how wargaming supports leadership education and analysis.
PostgreSQL Tutorial
Free tutorials covering PostgreSQL features, SQL basics, stored procedures, and advanced database functions.
DataCamp (Free R Tutorials)
While DataCamp is subscription-based, it offers free introductory R courses covering basics, data manipulation, and visualization.
Why Machines Learn
Anil Ananthaswamy
A deep dive into the elegant mathematical principles behind machine learning
PyBites Platform (Free Exercises)
Short, practical coding exercises (some free) focused on solving real-world problems in Python.
Power BI Community
Official Power BI community forum where users can ask questions, share solutions, and browse a large knowledge base of solved problems.