HTML

知乎上的一些Web基本概念介绍 http://www.zhihu.com/question/22689579

慕课网HTML+CSS基础课程 http://www.imooc.com/learn/9

w3school html教程 http://w3school.com.cn/html/index.asp

MDN HTML https://developer.mozilla.org/zh-CN/docs/Web/HTML/Introduction

CSS

MDN CSS https://developer.mozilla.org/zh-CN/docs/Web/Guide/CSS/Getting_started

w3school css http://w3school.com.cn/css/index.asp

慕课网HTML+CSS基础课程 http://www.imooc.com/learn/9

JavaScript

MDN https://developer.mozilla.org/zh-CN/docs/Web/JavaScript

慕课网JavaScript入门 http://www.imooc.com/learn/36

慕课网JavaScript教程 http://www.imooc.com/learn/10

w3school http://www.w3school.com.cn/js/

Codecademy http://www.codecademy.com/tracks/javascript