As nacs said but in other words, CodeMirror is syntax colored and directed code editing (emacs), while ProseMirror is wysiwyg text editing (word).<p>CodeMirror was started in early 2007. [1] ProseMirror is newer, announced July 7 2015 [2]. You&#x27;ve probably been using CodeMirror but didn&#x27;t even realize it -- it&#x27;s ubiquitous!<p>&gt;CodeMirror is an open-source project shared under an MIT license. It is the editor used in the dev tools for both Firefox and Chrome, Light Table, Adobe Brackets, Bitbucket, and many other projects [3].<p>Check out the CodeMirror JavaScript, HTML and Markup code folding demo -- who could say no to that? [4]<p>[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;CodeMirror" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;CodeMirror</a><p>[2] <a href="http:&#x2F;&#x2F;marijnhaverbeke.nl&#x2F;blog&#x2F;prosemirror.html" rel="nofollow">http:&#x2F;&#x2F;marijnhaverbeke.nl&#x2F;blog&#x2F;prosemirror.html</a><p>[3] <a href="https:&#x2F;&#x2F;codemirror.net&#x2F;doc&#x2F;realworld.html" rel="nofollow">https:&#x2F;&#x2F;codemirror.net&#x2F;doc&#x2F;realworld.html</a><p>[4] <a href="http:&#x2F;&#x2F;codemirror.net&#x2F;demo&#x2F;folding.html" rel="nofollow">http:&#x2F;&#x2F;codemirror.net&#x2F;demo&#x2F;folding.html</a>