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CSS
Cascading Style Sheets (CSS) is a simple mechanism for adding style (e.g.
20 Alternatives To CSS
C
One of the most widely used programming languages of all time
CoffeeScript
Unfancy JavaScript
Elixir
Dynamic, functional language designed for building scalable and maintainable applications
Elm
A type inferred, functional reactive language that compiles to HTML, CSS, and JavaScript
HTML5
5th major revision of the core language of the World Wide Web
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Haskell
An advanced purely-functional programming language
Java
A concurrent, class-based, object-oriented, language specifically designed to have as few implementation dependencies as possible
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JavaScript
Lightweight, interpreted, object-oriented language with first-class functions
Markdown by DaringFireball
Text-to-HTML conversion tool/syntax for web writers, by John Gruber
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OCaml
(* Binary tree with leaves carrying an integer.
Objective-C
The primary programming language you use when writing software for OS X and iOS
PHP
A popular general-purpose scripting language that is especially suited to web development
Perl
Highly capable, feature-rich programming language with over 26 years of development
Python
Python is a clear and powerful object-oriented programming language, comparable to Perl, Ruby, Scheme, or Java.
Ruby
A dynamic, interpreted, open source programming language with a focus on simplicity and productivity
Scala Lang
Scala is a pure-bred object-oriented language that runs on the JVM
Stylus
Stylus Studio is a fully featured and comprehensive suite for editing and developing in XML.
Swift
Swift is a general-purpose, multi-paradigm, compiled programming language developed by Apple Inc. for iOS, macOS, watchOS, tvOS, Linux and z/OS.