Adobe Brackets is an open source editor for open standard web languages (html/css/js/less/etc). It is totally free, and is a pretty exciting editor to try out. While Adobe says the editor isn't quite ready yet for prime-time, it can be a great tool if you are looking for a free open standards editor for web development. Written itself in html/css/js/less, Adobe Brackets aims to be incredibly extensible and is looking to build a community of contributors through GitHub.
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