This table was generated for TS12 and so contains a few keys applicable only in newer Trainz releases. Most of the table has been common across all Trainz Versions after Trainz UTC (V-1.5), and as with keys added in TS10 and TS12, keys added after that date such as the Camera Free Roaming External mode ('') just did nothing.
Historically, the Keypad keys were the controls used in Trainz 1.x, but that was unpopular given the need for the right hand on the mouse, which is perhaps busy even more often. With UTC a file "\Settings\keyboard.txt" was introduced allowing user customization of the keys which have remained stable until the introduction of new functional needs. The file keyboard.txt also allows the user to customize his Surveyorhotkeys as well as those useful in Driver.
Note except for Steam Loco Driving, the so called keyboard leftside cross (W, S, X, A and D) comprise the most often used Driver keys, those used for throttle control and the brakes. The Steam locomotive also heavily use F and R just to the right of the cross, as are less often used D, C, E, V and B keys.
There are 32 steps of acceleration in an electric locomotive, eight in a diesel locomotive, and hundreds of usable combinations of S+W (throttle) and R+F (cutoff angle) for Steam Loco driving modes. The Steam controls are effectively continuous functions using the mouse, while the keys increment or decrement values from those settings.