Usually learn programming or modules, there are many online help documents or manuals can be consulted, query, now put them down, again looking for more convenient.
Document class:
Crawler:
Scrapy1.2 Document: http://python.usyiyi.cn/translate/scrapy_12/index.html
Beautiful Soup 4.4.0 Chinese Document: http://beautifulsoup.readthedocs.io/zh_CN/latest/
Requests Chinese Reference manual: http://cn.python-requests.org/zh_CN/latest/
Html:
HTML Reference Manual: Http://www.w3school.com.cn/tags/index.asp
Sql:
SQL Quick reference: http://www.w3school.com.cn/sql/sql_quickref.asp
Python:
Python 2.7.12 Documentation (US): https://docs.python.org/2/index.html
Python 2.7 Tutorial (Liaoche): http://www.liaoxuefeng.com/wiki/001374738125095c955c1e6d8bb493182103fac9270762a000
R:
Java:
Data class:
Python Crawler Learning Series Tutorial: http://cuiqingcai.com/1052.html
The net of static searching (Technical talk is very good): http://cuiqingcai.com/
StackOverflow (It Technology FAQ website): http://stackoverflow.com/
Quora (FAQ SNS website): https://www.quora.com/
Datacastle (China's largest data science competition platform, with code share): http://www.pkbigdata.com/
PPV Course (website dedicated to data mining, data analysis, database course training): http://www.ppvke.com/
Disk lot (can search download ebook): http://www.panduoduo.net/
Laboratory Building (It Online education website): https://www.shiyanlou.com/
W3school (Web technology Tutorial): http://www.w3school.com.cn/
NetEase Cloud Classroom (online skill learning platform): http://study.163.com/
Garlic customer (programming, algorithm, computer theory online learning platform): https://www.jisuanke.com/
kaggle:https://www.kaggle.com/
POWER BI (Microsoft Data visualization artifact): https://zhuanlan.zhihu.com/p/22424022
Common technical online reference manuals and documentation