HTML: Hypertext markup language is used to define the structure of your web page. It is the tags and markup that help to add image, text, videos and other content to a webpage. The content enclosed within the tags is interpreted by the web browser and rendered as a webpage.
CSS: Cascading style sheets is used for adding style to web pages especially the fonts, colors, and spacing.
XML: Extended markup language is used for creating customized tags and markups for increased flexibility and easy passing of arbitrary data. XML is self-defining and self-describing that is the structure of the data is embedded in the data itself. So, when the data is received, there is no need to pre-build a different structure to store this data as the XML dynamically interprets it.
Web standards: Web standards are a set of rules and regulations that are set up by the World Wide Web consortium for the designing of the websites and web pages. The importance of adhering to these rules is that irrespective of the device in which the site is viewed the design will always remain consistent. The design features can be easily modified throughout the website by just making changes in one stylesheet and also, the search engine can easily index those websites that are designed to web standards.
Programming language: A programming language is a set of rules and pre-defined commands used for instructing the computing device to perform a specific set of operations.
Scripts: It is a computer language that is comprised of a series of commands within a file and is executed without compilation. The primary purpose of a script is for injecting some additional functionality to a web page or execution of heavy meatier tasks.