These flashcards contain the shapes used in Cangjie IME (input method editor) and the corresponding letters that they correspond to.
Cangjie is an IME that could have several advantages of pinyin input if you can learn the system. One of the advantages, for English speakers, is that you don't need to know how to pronounce a character to input it. Another is that you will not generally have to select characters from an alternatives list as you type, makin svg typing faster.
There are several resources on the web for learning the actual rules and principles of Cangjie, but this set of cards may be helpful in remembering the auxilliary forms in the beginning.