A useful tool for building regexes. It has a neat manual/library, examples, and resources for learning how to use Regex in various contexts and statements. Whenever I have the vast displeasure of using sed, I go here to build my matching statements.
When I was getting into ricing my command prompt, I hadn’t a clue how you’d go about achieving all those neat and impossible-looking terminal colors you see out int he wild. I still don’t, but I have built projects in the past that would suggest otherwise. Anyway, one day when I was a freshman in college I found this. I have no idea if this is even a good way to set colors anymore, but it’s pretty useful, and to this day, that’s how my terminal prompt works.