Optical Connector is a reusable passive component which could be applied in fiber and Cable connection. They are widely used in ODF, ODN,PON etc.
The ST connect was developed by AT&T shortly after the arrival of the FC. At a glance they can be mistaken for one another but the ST uses a bayonet fitment rather than a screw thread. Usage has declined in recent decades, for the same reasons as the FC. Additionally it cannot be terminated with an angled polish, which limits use in single mode fiber and FTTH applications.
Deployed predominately in multi-mode datacoms it is most common in network environments such ascampuses, corporate networks and in military applications where the quick connecting bayonet had its advantages at the time. It is typically installed into infrastructures that were built at the turn of the century; when retro-fitting, STs are typically swapped out for more cost effective SC and LC connectors.
OMC manufactures many sorts of fiber connectors. Such as SC,LC,ST,FC,MU,MTRJ,E2000 ,MPO,MTP,SMA,DIN,D4 etc.