What are SC connector and SC adapter?

http://en.wikipedia.org/wiki/Optical_fiber_connector#Types

It is listed towards the bottom of the table.

It is an acronym for Subscriber Connector of Standard Connector. It is a type of connector used to couple devices in home into a fiber-optic network. Here’s a picture.

I work with fiber optics, and ETpro is correct regarding the SC connectors. There is no adapter for connecting SC to anything other than another SC that I am aware of, except for light meters and OTDRs, and that kind of thing, though there are patch cords with different connections on either side.
However, I also use a module to connect wires, which is called an SC connector. There are probably a lot of different things with the SC label. Maybe you can tell us a little more.

@filmfann :

Thanks! so actually we need to connect/ align the center of a fiber towards a center of…let’s say a glass tube.. Is it still possible to do that? and which one do I use, the connector or the adapter? pardon me if I’m taking a long time to understand this as I’m really new to this stuff. Once again, thank you so much!

What is your light source, and what class is it?
of course you can aim a fiber optic strand towards the glass tube, but the light will disperse fairly quickly. What are you trying to do?