1. Patch cord is a fiber optic cable used to attach one device to another for signal routing.

Commonly, there are 4 types connector: FC/ SC/ LC/ ST. 3 types ferrule: PC, UPC, APC.

2. FC stands for Fixed Connection.

It is fixed by way of threaded barrel housing. FC connectors are generally constructed with a metal housing and are nickel-plated.

3. SC stands for Subscriber Connector - a general purpose push/pull style connector.

It is a square, snap-in connector latches with a simple push-pull motion and is keyed.

4. LC stands for Lucent Connector.

It is a small form-factor fiber optic connector, half the size of the SC.

5. ST stands for Straight Tip - a quick release bayonet style connector.

ST connectors are cylindrical with twist lock coupling. They are push-in and twist types.

6. PC stands for Physical Contact.

With the PC connector, the two fibers meet as they do with the flat connector, but the end faces are polished to be slightly curved or spherical. This eliminates the air gap and forces the fibers into contact.

7. UPC stands for Ultra Physical Contact.

The end faces are given an extended polishing for a better surface finish. These connectors are often used in digital, CATV, and telephony systems.

8. APC stands for Angled Physical Contact.

The end faces are still curved, but they’re angled at an industry-standard eight degrees. This maintains a tight connection. These connectors are preferred for CATV and analogue systems.