sgml

Rahul kundu

6th sem, IT

SGML

contents

Define what is SGML?

Advantage of SGML

Disadvantage of SGML

Define SGML

SGML stands for “standard generalized markup language”.

SGML, a system for organization & tagging elements of

document.

SGML developed & standardized by the international

organization for standard(ISO) in 1986.

SGML itself doesn’t specify any particular formatting; rather it

specifies the rules for tagging elements.

Define SGML cont….

SGML is not in itself a document language; but a description of

how to specify one. It is metadata.

SGML is a system for defining markup languages.

Author markup their document by representing structural,

presentational & semantic information along side content.


HTML is one e.g. of a markup language, here is an e.g. of an

HTML document:-

<!doctype HTML public “-w3c//dtd html 4.01//EN”

http://www/w3.org/tr/html4/strict.dtd”>

<html>

<head>

<title>my 1st HTML document</title>

</head>

<body>

<p>hello world!

</body>

</html>

http://www/w3.org/tr/html4/strict.dtd


above the HTML document is

divided into a head section & a body. The title of the document

appears in head & the content of the document appears in the body.

The body in this e.g. contains just one paragraph, marked up with

<p>.

o Every markup language defined in SGML is called an SGML

application.

o The language that this web browser uses, HTML is an e.g. of an

SGML based language. There is a document type definition for

HTML.

Advantages of SGML

1. Capable of dealing with any media type or linking protocol.

2. Extremely flexible

3. Separates content from appearance

4. Style sheets make content repurposing easy.

5. ISO standard- thus well supported with many tools available.

Disadvantages of SGML

1. Crating DTD’s requires exacting software engineering.

2. Linking tends to be complex.

3. Writing SGML software is extremely hard.

4. SGML tools trend to be expensive

5. SGML can be extremely complex and not widely used.

Thank you

sgml

Engineering