Markdown

Markdown-plus

http://mdp.tylingsoft.com/

stackedit

http://stackedit.io  GitHub(http://github.com/benweet/stackedit)

stackedit beta

http://stackedit-beta.herokuapp.com/

UML/Chart

flowchart.js

http://adrai.github.io/flowchart.js/

js-sequence-diagrams

http://bramp.github.io/js-sequence-diagrams/

CodeUml

http://www.codeuml.com/

YUml

http://yuml.me

draw.io (可视化编辑)

http://draw.io

Gliffy (可视化编辑)

http://www.gliffy.com

LucidChart

http://www.lucidchart.com

IDE

CodeBox

http://www.codebox.io

ACE

http://ace.c9.io

Cloud9

http://c9.io