Answer engine that cites its sources, so claims can be checked.

AI code completion inside your editor.

Upload your own sources and ask grounded questions about just those documents.

Searches academic papers and extracts findings into a comparable table.

Build and debug regular expressions with a live explanation of each token.

Complete offline office suite: documents, spreadsheets and slides.

Thousands of specialised calculators with the formula shown alongside.

Vast index of freely available programming books and courses by language.

Directory of free public APIs grouped by topic, with auth and HTTPS noted.

Step-by-step guides to rebuild real technologies from scratch to learn them.

Readable algorithm implementations across dozens of programming languages.

Open-source codebase behind the free full-stack curriculum.

Harvard's introduction to computer science, free to audit online.

Project-based web development curriculum with free certifications.

Free lessons and practice across maths, science and economics.

Visual step-by-step learning paths for developer and data roles.

Dense one-page cheat sheets for tools, languages and command lines.

Course materials, lecture notes and problem sets from MIT courses.

Free full-stack curriculum built around building real projects.

Bundle of developer tools offered free to verified students.

Reference manager that collects sources and generates citations.

Local-first markdown notes with linking and a large plugin ecosystem.

Spaced-repetition flashcards that schedule reviews for you.

Collaborative LaTeX editor in the browser with a free plan.

Builds clean, ATS-friendly resumes and exports them as PDF.

Docs, databases and wikis in one workspace with a free personal plan.

Visual mathematics explainers, including a clear neural-network series.

Full-length free course videos across programming and data topics.

Study technique and productivity videos aimed at students and professionals.

Press `.` on any GitHub repository to open it in a full editor in the browser.

Split-screen makes note-taking while reading much less painful.

Google Scholar alerts keep a literature review current without re-searching.

Collecting tiny tasks into one short block beats interrupting deep work.

Ad-free AI answer engine that summarises pages and never tracks you.

Ask one question and compare answers from many AI models side by side.

Assistant with strong reasoning and coding output on a free web tier.

Build web apps by chatting with AI, using your own provider API key.

Author- and publisher-approved free ebook offers, posted daily.

Free-to-watch documentaries, most of them hosted by the original broadcaster.

A maintained index of free courses, books and project ideas for beginners.

Historian-vetted reading lists organised by period and region.

Craft discussion plus a wiki of free tools, prompts and publishing advice.

Study systems, focus methods and free study resources from students.

Course coupons and permanently free classes posted by the community.

Computational answers for maths, science and unit-heavy questions.

Curated films and documentaries, free through participating libraries.

Tens of thousands of public-domain ebooks in open formats.

Borrow scanned books digitally from the Internet Archive's lending library.

Minimal typing test with detailed stats and no clutter.