HTML, CSS & JavaScript in easy steps

Mike McGrath

• Éditeur: In Easy Steps Limited
• Année: 2020
• ISBN:
  9781840789218
• Sujet: Conception
• Sous-sujet: Conception Web

HTML, CSS & JavaScript in easy steps instructs the reader on each of the three coding languages that are used to create modern web pages; HyperText Markup Language (HTML) tags are used to control the structure of web page content, Cascading Style Sheets (CSS) rules are used to determine how web page content appears, and JavaScript functions are used to provide web page interactivity.

HTML, CSS & JavaScript in easy steps contains examples and screenshots that illustrate each feature of all three coding languages. You'll learn how to create web pages to display text, images, lists, tables, hyperlinks, forms, audio, and video. Each chapter builds your knowledge so by the end of the book you'll have gained a sound understanding of HTML markup, CSS rules and JavaScript functions.

HTML, CSS & JavaScript in easy steps has an easy-to-follow style that will appeal to anyone who wants to create great functional web pages. It will appeal to programmers who want to quickly add web page coding to their skills set, and to the student who is studying website design at school or college, and to those seeking a career in web development.

1 Get Started in HTML

This chapter is an introduction to the exciting world of HTML. It demonstrates how to create a valid HTML document and how to include style rules, script code, and linked resources.

Meet HTML

Understand Structure

Create Documents

Validate Documents

Bestow Titles

Supply Metadata

Describe Contents

Add Styles

Include Scripts

Link Resources

Summary

Meet HTML

Historically, the desire to have text printed in specific formats meant that original manuscripts were “marked up” with annotation to indicate to the book printer how the author would like sections of text laid out. This annotation had to be concise and needed to be easily understood both by the printer and the author. A series of commonly-recognized abbreviations therefore formed the basis of a standard markup language.

HyperText Markup Language (HTML) is a modern standard markup language that uses common abbreviations called “tags” to indicate to the web browser how the author would like to have sections of a web page laid out. It was first devised in 1989 by British physicist Tim Berners-Lee at CERN in Switzerland (the European organization for nuclear research) to share all computer-stored information between the CERN physicists. Berners-Lee created a text browser to transfer information over the internet using hypertext to provide point-and-click navigation. In May 1990 this system was named the World Wide Web and was enhanced in 1993 when college student Marc Andreessen added an image tag. Now that HTML could display both text and images, the World Wide Web quickly became hugely popular.

As various web browsers were developed, their makers began to add individual proprietary tags – effectively creating their own versions of HTML! The World Wide Web Consortium (W3C) standards organization recognized the danger that HTML could become fragmented, so they created a standard specification to which all web browsers should adhere. This successfully encouraged the browser makers to support the standard tags. The final W3C standard specification of HTML5 is now continued by the Web Hypertext Application Technology Working Group (WHATWG) as the “HTML Living Standard”.

The World Wide Web comprises a series of large-capacity computers, known as “web servers”, which are connected to the internet via telephone lines and satellites. The web servers each use the HyperText Transfer Protocol (HTTP) as a common communication standard to allow any computer connected to any web server to access files across the web.

HTML web pages are merely plain text files that have been saved with a “.htm” or “.html” file extension, such as index.html.

You can find the HTML Living Standard specification, and other related specifications, online at whatwg.org

In order to access an HTML file across the internet, its web address must be entered into the address field of the web browser. The web address is formally known as its “Uniform Resource Locator” (URL), and typically has three parts:

•Protocol – any URL using the HTTP protocol begins by specifying the protocol as http:// or secure https://

•Domain – the host name of the computer from which the file can be downloaded. For instance: www.example.com

•Path – the file ...