It includes all the features you could ask for in a code editor, like a syntax highlighter, auto-detect for languages, automatic text completion, the possibility to use several panels and save your project to several folders, support for snippets, and a powerful search tool. The best feature is the modularity of the environment, to which you can add more features by installing extra packages. It also includes a control system for Git so you can publish your content using the GitHub platform.
Atom is multiplatform (Windows, Linux, and Mac) and allows cross-platform use for your projects. Customization is the IDE's biggest appeal: At time of writing, there are more than 2,000 packages and 600 themes. Given the degree to which you can customize the program and the number of features already included, this is definitely one of the best web development tools available today. What makes it even better is that it doesn't take up much space on your computer when compared to similar alternatives.