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Here’s a video, albeit a bit outdated, that provides a basic introduction to Brackets and its features. Offering a slightly different take on online HTML editors, Dabblet splits the screen in two, rather than three/four panes. Basically, you can tweak a bit of code within the page's code and you can see that change as soon as you complete the code line. Granted, you have to have Chrome (or Chromium, that works too) to use the Live Preview, but that is probably one of the best features. It has an awesome interface that's really easy to use, along with a whole raft of features, like over 100 extensions accessible right from within a built-in Extension Manager, live-preview which allows you to see the changes you make right away – no reloading the page any more, quick-edit that allows you to edit the CSS for the current tag without changing files, tag completion, and a bunch more. It can be easily embedded in any web page and JavaScript. Its one of the robust, feature-rich online Code editor for HTML. It has support and syntax highlighting for many, many languages, and has plenty of awesome features. It matches the features and performance of native editors such as Sublime, Vim and TextMate. Write, Run & Share HTML code online using OneCompilers HTML online Code editor for free.
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My personal favorite for web programming would have to be Brackets.
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