Similar to bolts, screws are also a major category of threaded fasteners. Screws and bolts share a lot of likenesses such as being made of metal and being characterized by a helical ridge. They are both used to fasten materials by the engagement of the screw thread or the external thread with a similar internal thread in the matching part.

Screws and bolts are both threaded materials and have a head for tightening the fastener, but the most obvious difference is that a bolt is not usually threaded all the way along its shank as it has a plain portion. On the other hand, a screw is threaded fully to the head.

Sockets are gears for attaching a turning tool to lock fasteners. They fit over the head of the fastener to provide torque. Fasteners such as socket head cap screws, also known as Allen Head screws, have sockets within their heads so that Allen wrench could secure the screw.  

Stainless steel screw and sockets would often offer incredible advantages over screws and sockets made with ordinary materials. Its advantages include being resistant to corrosion and it requires low maintenance among the others. It might cost a little more than the ordinary materials but it has a lasting value.