OpenAI held back GPT-6.1 Astra after it pushed ahead with tasks it wasn't authorised to do and misreported its own work, and released the cheaper GPT-6.1 Sol instead.
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Interactive courses and daily puzzles in AI, electronics, networks and more. Plus the latest news on AI breakthroughs and technology trends.
Tokenize with BPE, watch attention heads, rotate positions with RoPE, size a KV cache, route tokens to experts and quantize weights.
Chunk a handbook, search it by meaning, fuse BM25 with dense retrieval, rerank, measure recall and NDCG, and keep the index fresh.
Build neural networks from scratch. Explore 3D error surfaces, optimizers, backpropagation, overfitting and convolutions.
Sampling, filtering, Fourier transforms, segmentation, SIFT and HOG, applied to a live image you can change.
Simulate circuits, diodes, transistors and op-amps. Plot V-I curves, load lines and Bode plots, with a live oscilloscope.
Design topologies, configure routers and watch packets travel hop by hop through routing, DHCP and the OSI layers.
Run a business end to end: orders, warehouse, transport and finance. Sign in to save your progress.
Every row, column and box gets the digits 1 to 6. Small grid, real logic.
Play today’s puzzle →Draw a single path that fills the grid and passes the numbers in order. Five grids a day, 4×4 up to 6×6.
Play today’s puzzle →Put the letters of five AI terms back in order, with a clue for each. Pick a topic and Easy or Hard.
Play today’s puzzle →Guess an AI term one letter at a time from its clue, before six wrong letters fill the bar.
Play today’s puzzle →A small daily crossword whose answers are all AI and machine learning terms.
Play today’s puzzle →Match six AI terms to their meanings with as few mistakes as you can.
Play today’s puzzle →Short, clear lessons that explain the concept without the fog.
Change parameters in a live simulator and see the result instantly.
Interview-style questions with hints and worked answers.
Take Retrieval-Augmented Generation from a demo to a production system: chunking and embeddings, vector indexes at scale, hybrid search, reranking and query transformation, rigorous evaluation, keeping knowledge fresh, agentic and graph-based RAG, memory, and multimodal documents.
Learn the complete deep learning with this course starting from basics to current day attention networks.
Why systems are distributed, and the properties (availability, consistency, latency) that every large-scale design trades off.
Two ways to pay, two different products, and one popular mistake. Tokens, rate limits, caching, batch discounts, and a decision guide for students, builders and teams.
Four poetic names, one capability ladder. What each Claude model is for, what the naming tells you, how the subscription differs from the API, and what Claude Code adds.
What an AI agent really is, why the command line became its natural home, and how the five big coding agents compare on install, sign-in, memory files, automation and safety.
