Web Design with HTML and CSS

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CSS3 integration with HTML5

Web Design with HTML and CSS Digital Classroom

Web Workers.

The Web Workers framework addresses the issue of browser performance. When you access

advanced web applications, such as mapping or applications that generate charts and graphs

instantly, there are a number of processor-intensive computations that can slow down

the performance of your application. Much of the slowdown can be attributed to the

competition between the user interaction (clicking, dragging, and so on) and the need for the

application to access resources (graphics, data, and so on).

Web Workers are scripts that run in a separate thread. This separation means that processes

such as pulling data from a database can take place independently of user behavior and create

a more seamless environment for the user.

Web Storage

Web Storage is an upgrade to the current use of browser cookies. This is the process that

allows a web site to store small pieces of data on your system so the site can save information

for a later date. For example, sites that recognize your login information whenever you return

are most likely using cookies.

Cookies are a limited technology and not particularly easy for designers to use; Web Storage

aims to update the model to allow for greater storage space for modern web applications, as

well as to make the addition of storage features more accessible.

HTML5 provides two ways to store data: localStorage and sessionStorage. Data saved

as localStorage is available to the browser at any point, even if it closes or the user restarts

her system. Data saved as sessionStorage is lost as soon as the user closes that window.

Web Storage is an HTML5 feature used in Apple iPhones. The iPhone has a default storage

space of 5MB for data used in web applications, and as this space fi lls up, you receive a

prompt asking you to expand your storage.

CSS3 integration with HTML5

Many of the examples that exist online as HTML5 are a combination of the HTML5

technologies described above, JavaScript, and CSS. Most of the the CSS techniques you have

learned in this book are part of the CSS2.1 specifi cation. These fundamentals will continue

to be used, but the new and evolving specifi cations of CSS3 provide powerful new features

that work very well with HTML5. It goes beyond the scope of this book to cover these

features in depth but the following is a brief description of some of these elements.

• CSS Animations
  The ability to animate objects in the browser has traditionally been the role of
  technologies such as Flash; however, some of the same functionality can now be
  created using CSS rules and properties. The partnership of the HTML5 Canvas
  element and CSS3 transitions will potentially change the way designers create
  interactive and animated elements on the page.