examples of fittings [1]
Fittings are used to join two or more pipes, a pipe to a device, or a pipe to a cap or plug.
offset 
Fitting joining two pipes so that the pipe can bypass an obstacle.
U-bend 
Fitting joining two pipes in order to change their direction by 180°.
trap 
U-shaped pipe beneath a fixture containing a quantity of water to prevent sewage gases from escaping.
Y-branch 
Fitting joining three pipes, one of which is oblique to the other two.
tee 
Fitting joining three pipes, one of which is perpendicular to the other two.
90° elbow 
Fitting for joining two pipes in order to change their direction.
45° elbow 
Fitting for joining two pipes in order to change their direction by 45°.