A good web page designer will use % for height and width pixel definitions in Layout. It is wise and good design Principle to use % relative to main page layout. Also, images can be made responsive using max-width attribute of HTML img tag.

Since now a days display units come in different shapes and sizes including tabs and smart phones, it ensures your main page layout and it’s child elements will adjust automatically on all devices without distorting the layout and look and feel of the page.

It is called responsive designing of web pages and responsive design is one of the main Principles of Good Website Design. It ensures that you design once and use everywhere. If a website is designed in a responsive way properly, it almost eliminates the need of iOS or Android application.

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