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Ok let's keep going with the cool historical facts. On this day in 1971(!), the first email EVER was sent. It introduced the username@domain format we use to this day. So for today's coding challenge, you'll build a little email sorter. Go check out the rules and try to solve it on the freeCodeCamp mobile app.

AI agents are more useful when they can remember, use tools, and run from secure places. In this course, Shawn teaches you how to build a Telegram AI agent with Vercel, Cursor, and Composio. You'll add app integrations, long-term memory, mobile access, and scheduled tasks with Vercel Cron along the way.

Computers can perform calculations incredibly fast. But decimals can still trip them up. In this video essay, @ania_kubow explains why floating-point math can break money calculations. You'll learn why values like 0.1 and 0.2 are hard to store exactly, how rounding errors add up, and why financial systems use integers for currency.

Training larger AI models often means spreading the work across multiple GPUs. In this course, Kian explains Distributed Data Parallelism from the ground up. You'll learn about model parallelism, manual batch averaging, All Reduce, DDP hooks, plus the performance tradeoffs, too.

Generative AI systems can create content, like text or code, based on data they've been trained on. And in this bootcamp, @andrewbrown (and many other instructors) teach you key GenAI concepts. You'll get hands-on experience with Python data libraries, learn about prompt engineering, model fine-tuning, and AI agents, and lots more.

Most commercial voice assistants send your voice data to cloud servers before they respond. But if you build your own assistant with open source tools, you can run everything right on your phone. This gives you more privacy and control & Surya shows you how it works here.

You may have learned a lot of algorithms in your programming journey, but have you thought about why they work the way they do? Well, that's what you'll learn in this course. It goes into the mathematical reasoning behind an algorithm's performance and covers Divide and Conquer, probabalistic analysis, heaps, hash tables, and lots more.

WOAH. On this day in 1994 (so, like a bajillion years ago at this point, right?), Netscape Navigator was released. And today's coding challenge celebrates that with a fun little exercise. Check it out on the freeCodeCamp mobile app.

The field of Cryptography is all about securing both data and communication between systems. And in this course, you'll learn the basics like hashing, symmetric and asymmetric encryption, and more. By the end, you'll have built a fully-functioning Python-based command line cryptography tool.

Cloud-based LLMs are super powerful. But sometimes local models are a better choice, especially when you're dealing with sensitive info. Here, Manoj shows you how to use Ollama, Python, and LangChain to run LLMs locally and build privacy-first, AI-powered apps.

NVIDIA’s Certified Associate AI Infrastructure and Operations (NCA-AIIO) is an entry level certification. It tests your ability to run and manage AI systems. Here, you'll learn everything you need to pass the exam, including GPU architecture, ML, and more.

If you want to improve your technical writing skills, this course is for you. It'll help you make your writing more concrete and practical while teaching you to communicate clearly. You'll learn about framing definitions, describing objects and processes, writing formal reports, and more.

When you're building a website, you'll want it to be responsive, fast, and efficient. And there are many ways you can optimize the performance of your websites. In this handbook, @TanGuangzh54866 teaches you about server-side rendering, using a CDN, caching, file compression, image optimization, and more.

An Intrusion Detection System acts like a security camera for your network. And in this in-depth tutorial, @chairahalkar teaches you how to build a real-time IDS with Python. It'll alert you to any potential cyber attacks and security breaches so you can keep your network safe.

For today's coding challenge, you'll get a positive integer and you'll need to return a string with all the integers from 1 up to (and including) your integer. In numerical order. So like if you're given 5, you'll need to return "12345". Check it out on the freeCodeCamp mobile app.

Open source isn't just about the code. It's a community of contributors and maintainers coming together to build software. In this handbook, @AbdulTa62185243 goes over practical steps to help you find projects, make meaningful contributions, and grow your career.

Running LLMs locally has a lot of advantages. Like, it gives you access to AI capabilities offline and ensures data privacy, all without cloud costs. In this in-depth tutorial, @KraneOliver shows you how to set up, use, and customize popular models locally with Ollama.

If you get a context-related Flutter error, it's easy to just look up an answer on Stack Overflow. But if you don't really understand the three trees Flutter is built on, and what BuildContext is, you'll just keep googling. Here, @GiduduNicowalte gives you the guide he wishes he'd had to help you truly comprehend these errors.

Moving an LLM from prototype to production can introduce many security, privacy, and reliability issues. So Chidiebere is here to help you learn about and build a solid AI guardrail system. You'll build defensive layers with Python, prevent prompt injection, manage data access, and more.

Lots of web apps use badges for notifications, status labels, and so on. But a boring old static badge isn't enough these days. So adding some fun animations can really help. In this tutorial, @gupta05_vaibhav teaches you how to build an animated “success” badge using shadcn/ui, Tailwind CSS, and Framer Motion.