A screw is a short, thin and sharp pointed metal stick with a helical string circling it and an opened head. It is a sort of latch otherwise called bolt, used to combine things by being turned. So it pierces the wood or other material and is held firmly set up. A screw is designed majorly in three patters they are Partially threaded, Half threaded and Fully threaded.

Partial threaded

A Partially threaded screw has a smooth shank underneath its head and threads running along the rest of the screw's body. A partially threaded screw is used in applications where two bits of material must be combined firmly.

The top material is pulled along the smooth shank on the screw and braced to the base material. These sorts of screws don't require a leeway hole yet they may, in any case, require a pilot hole.

Half threaded

Half threaded screw is generally utilized where arrangement and shear protection is critical. This is because of the absence of strings in the grip length lends the screw amazing shear properties, as there are no ineffective focuses that could prompt splitting or bending. Gigantic forces are normally required so as to shear such a screw.

Fully threaded

As you may have thought, a fully threaded screw has no grasp length or string free segment. The strings keep running from under the head to the distance to the tip. 

Why pick a fully threaded screw?

In case you're most keen on hold quality and less inspired by arrangement and shear quality, a completely threaded screw will be the best choice. Once mounted, a full string screw spreads weight along its whole length, with the best holding weight put on the head where it meets the material to which it is attached.