Variable Type defines the variable as an input parameter, text parameter, or calculation.  It also defines the frequency (i.e. how often you can track the variable) such as Daily, Hourly, 15 Minute, 1 minute... of the variable.  The Variable Type is set by the Var Type and Track Every Fields on Variable Setup. 

WIMS currently supports the following variable types:
 P – Daily variable / parameter
 C – Daily calculated variable
 T – Daily text variable
 Z - Daily Picture Variable
 4 – Daily Detail variable tracked every 4 hours
 G – 4 hour calc.
 E – 4 hour text variable
 H – Daily Detail variable tracked every hour
 N – Hourly Calc
 B – Hourly Text
 3 – Daily Detail variable tracked every 30 minutes
 W – 30 Minute Calc
 Q – 30 Minute Text
 F – Daily Detail variable tracked every 15 minutes
 V – 15 Minute Calc
 X – 15 Minute Text
 5 – Daily Detail variable tracked every 5 minutes
 Y – 5 Minute Calc
 R – 5 Minute Text
 1 – Daily Detail variable tracked every minute
 S – Minute Calc
 A – Minute Text