Wikiversity course material about radiation, electromagnetism, and the physics thereof.

A single PHP file which acts as a basic ActivityPub server. This is designed to be a lightweight educational tool to show you the basics of how ActivityPub works. There are no tests, no checks, no security features, no header verifications, no containers, no gods, no masters. Needs only PHP v8.3 with OpenSSL turned on, an HTTPS certificate in for the web server, and about 50 megs of disk space for data storage.

I actively do not want you to use this code in production. It is not suitable for anything other than educational use. The use of AGPL is designed to be an incentive for you to learn from this software and then write something better. It is the nadir of bad coding. There are no tests, bugger-all security, scalability isn't considered, and it is a mess. But it works.

Many common and unusual algorithms, implemented in Python as learning exercises. If you want to get a sense of what, say, data structures or fuzzy logic would look like in Python, this is a good place to start.

CaskDB is a disk-based, embedded, persistent, key-value store based on the Riak's bitcask paper, written in Python. It is more focused on the educational capabilities than using it in production. The file format is platform, machine, and programming language independent. Say, the database file created from Python on macOS should be compatible with Rust on Windows.

This project aims to help anyone, even a beginner in databases, build a persistent database in a few hours. There are no external dependencies; only the Python standard library is enough.

Homemade circuits was started with an aim to share and spread the knowledge of electronic concepts freely among the aspiring engineers and newbies, through the expertise of experienced authors involved with this site.

The online world is flooded with multitude of electronic websites offering free electronic circuits and stuffs.. but unfortunately there's one thing they mostly seem to lack, and that's credibility. An electronic idea is not just about publishing a piece of schematic and forgetting, or posting something too technical without an elaborate and convincing explanation.

Here at homemade circuits, unlike others we make sure that the author who is writing the post has an in-depth knowledge regarding the subject, and actively responds to every comment or query posted by a inquisitive visitor. In this site you will find that no electronic concept is unnecessarily made complex just to make it look more advanced. We always try to produce an easier alternative if feasible, so that even a layman can feel inspired to learn more.

The Selfie Project provides an educational platform for teaching undergraduate and graduate students the design and implementation of programming languages and runtime systems. The focus is on the construction of compilers, libraries, operating systems, and virtual machine monitors. The common theme is to identify and resolve self-reference in systems code which is seen as the key challenge when teaching systems engineering, hence the name.

Selfie is a self-contained 64-bit, 11-KLOC C implementation of:

• a self-compiling compiler called starc that compiles a tiny but still fast subset of C called C Star (C*) to a tiny and easy-to-teach subset of RISC-V called RISC-U,
• a self-executing emulator called mipster that executes RISC-U code including itself when compiled with starc,
• a self-hosting hypervisor called hypster that provides RISC-U virtual machines that can host all of selfie, that is, starc, mipster, and hypster itself, and
• a tiny C* library called libcstar utilized by selfie.

Selfie generates ELF binaries that run on real RISC-V hardware as well as on QEMU and are compatible with the official RISC-V toolchain, in particular the spike emulator and the pk kernel.

Usborne children's coding books for a new generation. There are some classics in here, too.