- Global Variables (per project). Optimally there should be two kinds: static and non-static (static keep their last value between runs). Each variable should be able to hold all the main variable types (string, int, decimal etc.)

- Local Variables (per web test)

- Local Parameters (per web test)

Those get used within the test and can be supplied easily through the GUI when calling a test as a step (optimally should offer to supply a value, a parameter, a variable or an extracted variable).