Pouring is a function in OE-Cake, in which a material is created in the top of the screen. Wall will be removed and Rigid particles will not stick, the material becomes a liquid. Elastic and String will retain most of their connections, however. The function is activated by using (shift) + the material's letter, usually the first letter of their name. Then, the corresponding element will shoot out from the top of the screen. Example: type J for liquid jet, O for liquid outflow, R for liquid rigid, etc. This also works with Caps Lock.
As long as there is no User on the screen, the left/right arrow keys will adjust the pour position and the up/down keys will adjust pouring volume.
Pouring is somewhat less useful than Inflow, because you can only Pour pure elements, never mixed combos or colored materials, and it's always stuck to the top of the screen. It is still useful because it generates infinite pressure, because Inflow can only generate relatively low pressure.
For more, see Tools.