Question: What different technologies are there to make a website responsive?
2.There are additional tools like jQuery that can-do things like detect the type of device that the user is on. You can use tools like Masonry to control the layout of things like image galleries. Grid systems like Twitter Bootstrap, Zurb Foundation, or Pure CSS (by yahoo) can be used to re-arrange your content if you have a very basic site.
4.To give you a simple answer, you have to understand content. I have this argument with almost every web designer, understanding content is more important than understanding programming when planning a responsive site.
5.To give you a simple technical answer, you need to plan your grid starting with mobile. Then factor in that this grid will expand allowing you to let those images either expand or to be replaced with a larger image, then you can rearrange placement of elements or bring in content that is only intended for larger screens, for example a side bar that serves ads for desktop users only.
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