File upload

DropzoneJS is an open source library that provides drag’n’drop file uploads with image previews.
Dropzone.js
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Dropzone.jsis a light weight JavaScript library that turns an HTML element into a dropzone. This means that a user can drag and drop a file onto it, and the file gets uploaded to the server via AJAX.

All avalible options and full documentation you can find: http://www.dropzonejs.com/#configuration-options