Each correction, enhancement or effect is implemented as a module. This section includes documentation of each module and its specific parameters.
A module has an expander bar 
.
Clicking on the name of the module expands the module's GUI with all parameters. If you expand too
many GUIs you may easily lose track - it's up to the user to do the housekeeping. Alternatively you can expand the
module's GUI with shift-click, which expands just the desired GUI while collapsing all others.
Expanding a module does not activate it. You need to click the 
icon to turn a module on or off.
Icon 
accesses the
module's available presets or creates a new preset from your current settings (see Section 3.4.4, “Module presets”).
The 
icon is used to reset the module parameters to their default values.
Many of darktable's modules can have multiple instances, each with different settings. Click on the
icon to generate new instances and control
existing ones (see Section 3.4.5, “Multiple instances”).
The most frequently used control elements are sliders, comboboxes and curves.
For each slider, you can interact in four different ways, depending on the level of control you need.
Triangular marker
Left-click the slider's triangular marker and drag it to the left or right.
Mouse wheel
Hover over any place on the slider with your mouse, then use your mouse wheel to adjust the value step by step.
Right-click
When your mouse is over a slider right-click gives you a multi-functional pop-up below the slider for fine control with your mouse or numerical entry using the keyboard, there is no cursor, you just start typing.
darktable's innovative input method: for both coarse and fine value adjustments in a single control element. 
A bent line extending from the triangular marker moves as you move your mouse. The closer your mouse pointer is to the triangular marker the coarser the control; the further away from the triangular marker the finer is your control. Left-click with your mouse to accept the current value and go back to normal control.
Double-click
You can double-click on a parameter label to reset its value to default.
Clicking on a combobox will open a list of available options. Click on the item you want to select. Sometimes the selection list opens close to the bottom or top of the screen and only part of the items are visible; scroll with your mouse wheel to bring up the full list.