Here‘s a Khan Academy video series that goes over how encrypted communications work.
Here‘s my attempt to clear up some confusion people have about Newton’s laws of motion.
Here‘s a book about programming on Unix and Linux. This has some very handy tips for programming anything and designing things in general. In all honesty I haven’t finished the whole thing yet (it’s pretty long); however it still has some useful info.
Here‘s a tutorial on how to make a “universal robot gripper” which can pick up nearly anything.