An Open Web App is basically an HTML5 app. While the role of HTML, CSS, and JavaScript are obvious to some, let's do a quick recap of how each plays its own important role in an HTML5 app.
HTML5 for content and structure
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HTML is used to create the content structure for the web application. New features in HTML5 include new |
CSS3 for style
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CSS provides the visual presentation, letting you control the basic layout of content. CSS can do more than just format content though; you can use the power of CSS to animate elements, create precise gradients to avoid having to unnecessarily use images, and create media queries which let you adjust the appearance of your content based on the type of device it's being viewed on. |
JavaScript for dynamic interaction
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JavaScript provides the level of dynamism and user interaction for the web app. JavaScript lets you listen for and respond to user interactions, load content dynamically, and get access to device-specific features, like the Camera API and Geolocation API. |
It's important to note that support for individual features varies from browser to browser; feature detection and research should be done before using each feature. How to use these strategies will be covered in depth below.