Input Hanzi on computers

1. Type online (no need for downloading or change setting, only need the internet connection)
http://chinese.cari.com.my/ime/py21000.html
http://chinese.cari.com.my/ime/
http://www.chinese-tools.com/tools/ime.html
 http://pinyin.sogou.com/cloud/?r=pinyin (Sougou cloud input, not working online any longer, now need to download, 09/2014 )
 
2. Tutorial for installing Chinese Input in Windows system
 (change the local computer setting, no need for the internet connection)

Control panel > Clock, Language and Region > Region and Language > Change Keyboards or other input methods > under the Tab  Keyboard and Languages > Change keyboard > Chinese (simplified) -Microsoft Pinyin

3. Download Google Pinyin for Windows system: (after downloading, no need for the internet connection)
http://www.google.com/ime/pinyin/

Chinese input in MAC
http://www.yale.edu/chinesemac/pages/input_methods.html