Difference between revisions of "Standard Generalized Markup Language (SGML)"
| Line 5: | Line 5: | ||
*The document type definition (DTD). The DTD defines the syntax of markup constructs. The DTD may include additional definitions such as numeric and named character entities. | *The document type definition (DTD). The DTD defines the syntax of markup constructs. The DTD may include additional definitions such as numeric and named character entities. | ||
*A specification that describes the semantics to be ascribed to the markup. This specification also imposes syntax restrictions that cannot be expressed within the DTD. | *A specification that describes the semantics to be ascribed to the markup. This specification also imposes syntax restrictions that cannot be expressed within the DTD. | ||
| − | *Document instances containing data (contents) and markup. Each instance contains a reference to the DTD to be used to interpret it.<ref>Definition - What is | + | *Document instances containing data (contents) and markup. Each instance contains a reference to the DTD to be used to interpret it.<ref>Definition - What is Standard Generalized Markup Language (SGML)? [https://www.w3.org/TR/WD-html40-970708/intro/sgmltut.html#:~:text=The%20Standard%20Generalized%20Markup%20Language,such%20%22application%22%20of%20SGML.&text=Document%20instances%20containing%20data%20(contents,be%20used%20to%20interpret%20it. W3.Org]</ref> |
Revision as of 19:00, 26 January 2021
The Standard Generalized Markup Language (SGMl) as defined in ISO8879, is a language for defining markup languages. HTML is one such "application" of SGML.
An SGML application consists of several parts:
- The SGML declaration. The SGML declaration specifies which characters and delimiters may appear in the application.
- The document type definition (DTD). The DTD defines the syntax of markup constructs. The DTD may include additional definitions such as numeric and named character entities.
- A specification that describes the semantics to be ascribed to the markup. This specification also imposes syntax restrictions that cannot be expressed within the DTD.
- Document instances containing data (contents) and markup. Each instance contains a reference to the DTD to be used to interpret it.[1]