Designing a responsive and user-friendly website is not an easy task. It requires lots of effort, and you need the correct language to use.
The two famous languages used in website design are SGML and the other one is XML. They have got separate features and have both advantages and disadvantages. XML is also derived from SGML. But it has some amazing features.
Key Takeaways
- SGML is a markup language for creating document types, while XML is for structuring data.
- SGML is complex and difficult to use, while XML is simpler and more flexible.
- SGML has been largely replaced by XML in modern web development.
SGML vs XML
SGML is a markup language used majorly in large-scale document management systems, such as in the publishing industry. It is a powerful and flexible language. XML, is a markup language, developed to be simpler and more flexible. It has become a widely-used standard for data interchange on the web.

SGML is a markup language used by IT people. It is popular among markup languages. It is an extension of the HTML language.
But the features, coding part, and stylesheets used in SGML are entirely different from HTML. The subset language of SGML is XML. The subset was first designed for the world wide web but is now used in unrelated areas.
XML is a language used in the back of HTML for simplifying the creation of large websites. It does not come under any programming language type as it has no separate vocabulary and grammar rules to perform them.
You can store the XML in a simple text file. For interpreting XML, you need to have special software. It will not be replaced with HTML, but it has got some new features that can be used alongside HTML.
Comparison Table
Parameters of Comparison | SGML | XML |
---|---|---|
Language | It is a meta-language | It is a markup language |
Features | It has complex and also requires overhead to use it | It does not have complex and overhead for use |
Data Validation | It does not allow data validation | It allows data validation |
Datatag declaration | It is allowed in SGML | It is not allowed in XML |
Empty start tags | They are allowed in SGML | They are not allowed in XML |
What is SGML?
SGML is an expansion of Standard Generalized Markup Language. HTML is an application that is used in SGML. It is used for marking up documents. It is independent and now dependent on any specific application.
SGML is derived from GML, which is nothing but Generalized Markup Language. With the help of this, users can work on standardizing different formatting styles for their electronic documents.
It is unique because you can write your markup schemes.
SGML consists of three main components such as SGML declaration, document instance, and Prolog. SGML helps you to encode the full structure of the document. Also, it supports any media type.
It would be a good use of HTML as it has the capability of visual code representation. It can separate the content from appearance.
It allows for more complex formatting. This feature is not available in SGML. That is the main reason why many people prefer SGML over HTML.
SGML contains stylesheets that help to make the content used for different purposes. It is extremely flexible. Because of the ISO standard, it has got many well-supported tools.
However, it has got some disadvantages as well. Nothing comes with a full advantage. To code in SGML will be very typical and difficult as well.
SGML tools are always expensive. To display the document, you must install some special software in your system.

What is XML?
The expansion of XML is an extensible markup language. The reason why it is created is for storing and transporting data. It is very similar to the HTML language.
It is used for representing documents, books, invoices, transactions, and many other things. It is also used in asp.net for ad rotator and some other features. The XML language has many uses and is incorporated into building many websites.
It is derived from an old standard format of SGML for making web pages more responsive. Many people call this a cousin to HTML. It helps to conduct complex business over the internet.
It is extensible, which means you can create the stages and language for your application. It is used to carry the data and will not present it.
You can store the data irrespective of how the data is being presented. It was developed by the world wide web consortium. Therefore, it is an open standard.
You can customize your data handling needs with the help of XML, as it allows you to store and arrange the data. For creating any desired or specific output, you can always merge them with the stylesheet.
You can also express any data in the XML document. For reloading and offloading databases, you can use XML.
You can easily exchange information between the organization and systems. It will work behind the HTML and make the website more attractive and responsive.

Main Differences Between SGML and XML
- The language used in SGML is meta language. On the other hand, the language used in XML is a markup language.
- SGML has complex and overhead features which allow you to use them. On the other hand, you cannot find these features in XML, and it will not allow the user to use them.
- SGML will not allow the user to use data validation. On the other hand, XML allows the user to use data validation.
- Datatag declaration can be used in SGML. On the other hand, Datatag declaration cannot be used in XML.
- Empty start tags are used in SGML. On the other hand, empty start tags are not used in XML.
- SGML stands for Standard Generalized Markup Language. On the other hand, XML stands for eXtensible Markup Language.