Tools
Code Editors
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gedit
official text editor of the GNOME desktop environment
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Notepad++
Free source code editor and Notepad replacement that supports several languages.
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Text Wrangler
HTML and text editor with code folding, syntax coloring, and extensibility.
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Sublime
Sophisticated text editor for code, markup and prose. Extendible with plugins adding powerful features, snippets and more.
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TacoHTML
HTML editor and PHP editor which includes syntax checking as well as organising code indentations.
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Espresso
Powerful code editor with extensive language support, contextual completions, powerful smart snippets, and Zen actions.
Coding Tools
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Dabblet
An interactive CSS playground and code sharing tool, created by Lea Verou
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Codepen
HTML, CSS, and JavaScript code editor in your browser with instant code previews, created by Chris Coyier, Tim Sabat and Alex Vazquez.
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jsBin
JS Bin is a JavaScript, HTML and CSS playground with instant previews, built and shared by Remy Sharp.
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jsFiddle
HTML, CSS, and JavaScript code editor with immediate code previews, created and maintained by Piotr and Oskar.
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Prefixr
Cross-Browser CSS in Seconds!
created by Jeffrey Way -

Gradient-Scanner
Open an image that contains a gradient and then draw a line over the major components of the gradient.
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Gridpak
The Responsive grid generator with ready-to-use download,
created by Erskine Design
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