Some things that I've found useful.

Web Development:

MDN -- Web docs. Probably the sanest place to find them short of reading specs directly.

Rust:

Install Rust, and then use

$ rustup doc

The rust book, included with the install of rust, has a tutorial inside it. The included API reference is equally excellent, although not a tutorial.

C:

Beej's Guide to C Programming -- What it sounds like. Book length document covering the C language.

Godot:

Grabbed these links when helping set up a friend with Godot.

Official "First Game" Tutorial -- A decent intro to Godot. David Epesce's Godot Tutorials -- I like these. Walks through making a top down RPG.

General/Other:

Beej's Guide to Network Programming -- What it looks like. Examples are in C.