HTML

            HTML or Hyper Text Markup Language is the main markup language for creating web pages and other information that can be displayed in a web browser.Hypertext Markup Language is the set of markup symbols or codes inserted in a file intended for display. The markup tells the web browser how to display a webpage’s words and images for the user. Each individual markup code is referred to as an element (also known as tag). The idea and terminology evolved from “marking up of paper manuscripts”.

     HTML is written in the form of HTML elements consisting of tags enclosed in angle brackets (like ).HTML tags most commonly come in pairs and some tags represent empty elements and so are unpaired. The first tag in a pair is the start tag, and the second tag is the end tag (they are also called opening tags and closing tags). In between these tags web designers can add text, further tags, comments and other types of text-based content.

HTML 1

          This is the first version of HTML introduced in 1989. It supported inline images and text controls. HTML 1.0 was very limited in terms of styling and presentation of content. Does not support use of, tables or frames, specify fonts, change page background, or use forms. It have Limited styling and presentation of content. As there was no option to change the background every page written in HTML 1 looked similar.

HTML 2

The first HTML specification intended to be treated as a standard against which future implementations should be based. It included features such as headings, lists, anchors etc. It included forms with limited set of form elements such as text boxes, and option buttons and provision to change of page background and also included use of tables.

HTML 3

The first version developed and standardized by World Wide Web Consortium. It is an SGML application. The syntax of html 3 is a combination of the SGML declaration and Document Type Definition (DTD). This version included support for creating tables and expanded options for form elements and also allowed web pages to include complex mathematical equations.

HTML 4

This version released in 1999 added support for style sheets and scripting abilities for multimedia elements. It focused on separating presentation styling information from the actual content by the use of style sheets. It composed of three parts

·         Line containing html version info.

·         Declaration header information.

·         Body

HTML 5

It is the fifth revision of the html standard. The core aims have been to improve the language with support for the latest multimedia. It is also a potential candidate for cross-platform mobile applications. Used for applications and mobile websites on mobile OS such as Firefox OS, Tizen and Ubuntu touch. HTML has not been addressed to web applications. This specification attempts to rectify this.

            Many features of HTML 5 have been built with consideration being able to run on low-powered devices such as tablets and Smartphone.

MARKUP

HTML 5 introduces elements and attributes that reflect typical usage on modern websites. Some of them are semantic replacements of common uses of  generic block(

)

and inline () elements, for example 

(website navigation block), 

 (usually referring to bottom of web page or to last lines of HTML code), or  and instead of Some deprecated elements from HTML 4.01 have been dropped, including purely presentational elements such as  and whose effects have long been superseded by the more capable Cascading Style Sheets. The HTML5 syntax is no longer based on SGML despite the similarity of its markup.

NEW API’s

Canvas element

The canvas element is part of the html for dynamic scriptable rendering of 2d shapes and bitmap images.

Timed Media playback

Timed media sis very dynamic and offers many changes to tackle with. Before HTML 5 it was flash. Formats supported are H.264,ogg and webM. Track elements allows specifying the tracks for media elements.

Offline Web Applications

A web browser that implements HTML5 offline application will read the list of URLs form the manifest file, which is just a text file located elsewhere on the web server, download the resources cache them locally and automatically keep the local up to date as it change.

Document editing

Drag and Drop

 In HTML 5 drag and drop is a part of standard and any element can be draggable.

Cross-Document messaging

Web browsers for security and privacy reasons, prevent documents different domain from affecting each other, that is cross-site scripting is disallowed. Messaging system allows documents to communicate with each other regardless of their source domain, in a way designed to enable cross-site scripting attacks.

Browser history management

Manipulate the browser history via script. Include a way to add entries to the browser history to visibility change the URL in the browser location bar (without refresh) and an event that when those entries are removed from the stack by user pressing the browse back button.

MIME type and protocol handler registration

An internet media type is a standard identifier used on the internet to include the type of data that a file contains.

Microdata

To allow generic svripts ti provide services thr are customized to that page.

Webstorage

Used to store  name value pairs on the client side.

WebRTC

The RTC in WebRTC stands for Real-Time Communications, technology that enables audio/video streaming and data sharing between browser clients (peers). As a set of standards, WebRTC provides any browser with the ability to share application data and perform teleconferencing peer to peer, without the need to install plug-ins or third-party software. 

Web workers

Dedicated Web Workers provide a simple means for web content to run scripts in background threads. Once created, a worker can send messages to the spawning task by posting messages to an event handler specified by the creator.

Notification

The Notification object is used to configure and display desktop notifications to the user.

Some related technologies, which are not part of either the W3C HTML5 or the WHATWG HTML specification, are as follows.

Geolocation : Geographical Location information for a client side device.

Web SQL Database: Web SQL Database is a web page API for storing data in databases that can be queried using a variant of SQL.

The Indexed Database API: The Indexed Database API, or Indexed DB (formerly WebSimpleDB), is a proposed web browser standard interface for a local database of records holding simple values and hierarchical objects.

HTML5 File API: HTML5 File API aspect provides an API for representing file objects in web applications and programmatic selection and accessing their data. In addition, this specification defines objects to be used within threaded web applications for the synchronous reading of files.

Directories and System: This API is intended to satisfy client-side-storage use cases not well served by databases.

File Writer: an API for writing to files from web applications.

Web Audio API : A high-level JavaScript API for processing and synthesizing audio in web applications.

Error handling : HTML5 is designed so that old browsers can safely ignore new HTML5 constructs.

Popularity

According to a report released on 30 September 2011, 34 of the world's top 100 Web sites were using HTML5 – the adoption led by search engines and social networks. Another report released in August 2013 has shown that 153 of the Fortune 500 U.S. companies already implemented HTML5 on their corporate websites.