I’ve always thought anything that is sever side is back-end since it’s dealing with the actual processing of data (*) and such while front-end merely is a UI for someone to mess around with. That’s why anything client related can be modified without the original author’s permissions while anything from PHP, ASP.NET, Ruby, Python, and the such cannot and has to be exploited using such methods.
I’ve always thought; HTML, CSS, Javascript, images, and anything “asset” related are front-end while server-side like the above and Scala are back-ends?
If you guys ever read the e-book Sitepoint has given (Javascript: Novice to Ninja), it gives an analogy in the beginning of the first few chapters about the 3-layered pizza. 1st layer is HTML and it’s the base of the pizza. 2nd layer is CSS and that’s basically the sauce and cheese on top. 3rd and last layer is Javascript which is your toppings and whatever you want on the pizza.
Or how I’ve always thought of it like a human body.
1st part is the skeleton which is your HTML, it basically holds the body together. Without this, the body cannot move or function like it should or we would all be wobbly creatures. 2nd part is your skin and the shape of your body and what not, it makes you how you look which is what CSS basically does. It makes your web page look beautiful and what not. And lastly, your nerves and body functionality. It makes your body work like it does. Without this, you can’t tell your arms to move left when you want it to or move right when it should. That’s basically how Javascript works. Without Javascript, you can’t make a button submit the form without refreshing the page.
I’ve always though those are the 3 main building blocks of a “front-end”.