Pinyin table list all pinyin symbol, its English letter for keyboard input, type(Initial-I, Finals-F, Unique PinYin rule-U), its sequence order in that type, and further we group them for beginner to memorize them.

It has the following fields :

Pinyin symbol  Text field Yes  
English letter  Text field Yes  
Type  Menu field I F or U
Group  Menu field No  
Audio  File field No  
Ordering  Number field No
Spelling_rule  Text field No

Pinyin symbol: u
English letter: U
Type: F
Group: 1
Audio: Audio file (MP3) u.mp3
Ordering: 5
Spelling_rule: WU without initial, u does not work with j、q、x、y, those u are actually ü。