These are types of internet coding languages. Sites often need to change their programming for various reasons, and code needs to be converted into a variety of languages. Its common for databases to need to convert part of their code into SQL to be able to run search queries more efficiently as well. Converting word files to HTML files is also important if those files will go on web pages.

XML is exntensible markup language and is a set of rules for encoding documents electronically. XML provides for a wide variety of structural formats. XML is very flexible in a way that enables authors to add tags, and their own attributes and elements.

SGML is standard generalized markup language which preceded HRML and is a standardized language for the descriptive markup of documents.

HTML is a standard language for page creation on the internet. There are easy commands to give within <> brackets to indicate color, font, spacing, size, bold, links, and more. HTML is not difficult, and basic commands can be learned in one day.