If you are a Siemens PLC user then you've more then likely have run into Statement List (STL) programming. STL corresponds to the Instruction List language defined in the IEC 61131-3 specification. The programming is done with very simple mnemonics that can be hard to remember if you don't use it very often.
These cheat sheets provide a quick reference guide for all the instructions and formatting. They are two pages long but if you can print on the front and back then they make for a nice one sheet reference.
STL Listed Alphabetically
Best used when trying to interpret an existing program.
Download:
PDF (131KB)
STL Listed by Category
Download : PDF