Hi all! I'm pretty new to HTS, but I'm really excited to get going! I'm guessing that the answers I'm looking for are somewhere on here already but I don't feel like looking through 50+ pages of a forum... =0
Anyway, I was wondering, I think I have a pretty good Idea of what I need to do on mission 7, (type a unix command into Sam's script so it will show me the password file) but I just wanted to know a few things first. What is Unix? I'm guessing it's a programming language but what is it used for, and how (generally) does it operate and what are a few good commands to start with? That brings me to another question I've been wondering a lot recently, but where is a programming language used? Is it like a computer reads a certain language, a website reads a certain language, a program, all of the above? Or does it depend on wich programming language it is? Thanks in advance guys.
Unix is an operating system, much like Microsoft Widows is. This operating system is what (I think) Mac OS X runs as it's kernel (the brain of the operating system). Because Unix cost quite the pretty penny, back in the 80's a guy called Linus Torvalds wrote a clone of Unix called Linux. This operating system is what either the majority of the people here run, dual boot, or at least have experience with. If you want to get that experience for yourself, download a virtual machine (VirtualBox
), a version of Linux (Ubuntu
) and try it out for yourself!
Also, a programming language is ALWAYS run on the computer. It may not be your computer, it may be a server somewhere else, but it ALWAYS runs a on a computer. Computers themselves are essentially a bunch of On/Off switches, similar to those that you use to turn on a light... except that this switch is controlled by the flow of electricity, (no electricity = off, electricity = on) instead of a finger, and that they're microscopically small. However, unless you want to manually turn on every single switch that's required to display an image (approximately 2895600 of them), you need something to do it for you. This something is what is known as binary. You know, those 1's and 0's you see in all the fake TV shows? Yeah, that. A 1 represents power to the switch, and a 0 represents off. Hurray! You can do it automatically... sort of. You still have a problem, though; you need to write either a 1 or a 0 for each switch you want, which is hardly easier than switching them yourself.
Because people are lazy, we invented another language called Machine Language. This language is MUCH easier than writing in pure binary, as it allows you to name variables, place variables in certain parts of the computer, and just generally be a badass. The downside to this language is that it is, as the name implies, not very human-friendly, and as such is hard to write in. Thus, even lazier people developed a language called assembly language. This makes machine language human friendly, and still is WAY easier than writing in binary. The only down side to it, is it's still about just as time consuming as writing in machine language. People wanted something that they can write fast, instead of it taking maybe a day or two, to get a simple program working. And, as we've learned, programmers are lazy, and so they just kept inventing easier, and easier languages until we have the ones we do today.
Don't be confused, though, the computer itself never changed what it reads (binary). But because we are now developing in such easy (high-level) languages, they have to be translated into binary somehow, no? Well, there's two things that do that; one, something called a "compiler" that turns whatever language you've written into assembly language (remember it's that thing that was just a step above machine language). Then, a thing called an "assembler" turns that assembly-language into machine language, and then your processor (CPU (the brain of the computer)) turns that into binary, all by itself. This process happens inside every computer, in every language, constantly. You think that HTML that you're writing will be run in the web browser? Nope. The web browser is being run by the computer, so, the HTML is indirectly being run by the computer. Hope that helps clarify some things. TL;DR:
Just read the damn post.