MakeHuman is based on parametric modelling, controlled by sliders.
The meaning of each slider is generally self explanatory. Each slider controls the amount of a feature is expressed in the character from its minimum value to is maximum value. For example, the slider "Age" will change the character from the minimum age, which is about 2 years old, to the maximum age of about 80. When multiple sliders are moved, the values are mixed to form a character that reflects the user's chosen settings using a special interpolation engine. Each slider can be reset individually with right click on it.
A slider normally moves in increments of 3 or 4 setting values when dragged with the mouse; however, you can place the mouse cursor over the orange portion of the slider and use the mouse scroll wheel to make adjustments in smaller increments of 1.