Editing HTML (section)

===New Features of HTML 5===
#[[#Web_Storage|Client side DBs/storage (local storage)]]
#better performance with JavaScript 1.6
#[[#Offline_Cache|cache for offline times and to avoid Http request]]
#form attributes
#[[#Custom_Data_Attributes|'''data-'''* attribute for each HTML element (* means free choice)]]

====Viewport====
The viewport is the area in which a web page is drawn. It can be defined  using the "viewport" property in an HTML <meta> tag or in [[CSS#Viewport|CSS]].
====Web Storage====
With local or web storage, web applications can store data locally within the user's browser. Before HTML5, application data had to be stored in cookies, included in every server request. Local storage is more secure, and large amounts of data can be stored locally, without affecting website performance. Unlike cookies, the storage limit is far larger (at least 5MB) and information is never transferred to the server. Local storage is per origin (per domain and protocol). All pages, from one origin, can store and access the same data.

The Web Storage API contains two new objects:
#window.localStorage: storage without time limit
#window.sessionStorage: storage for a session (data will be deleted, when the tab is closed) 

For an implementation see [[jStorage|jStorage]].

====Offline Cache====
HTML5 introduces application cache, which means that a web application is cached, and accessible without an internet connection (see [https://www.html5rocks.com/de/tutorials/appcache/beginner/ here]). To enable application cache, include the manifest attribute in the document's <html> tag. The manifest file is a simple text file. For the structure and content see UweHeuer project \src\web\mobile.appcache.

====Custom Data Attributes====
The specification for custom data attributes states that any attribute that starts with “data-” will be treated as a storage area for private data,in the sense that the end user can’t see it – it doesn’t affect layout or presentation.
To get a data attribute through the dataset object, get the property by the part of the attribute name after data- (note that dashes are converted to camelCase).

 var x = article.dataset.<attribute-name without data- prefix>;